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href="#alzheimer.Clinical_Characteristics_of_Al">clinical characteristics</a> of Alzheimer disease (AD);</p></dd></dl><dl class="bkr_refwrap"><dt>2.</dt><dd><p class="no_top_margin">Review the genetic <a href="#alzheimer.Causes_of_Alzheimer_Disease">causes</a> of AD;</p></dd></dl><dl class="bkr_refwrap"><dt>3.</dt><dd><p class="no_top_margin">Provide an <a href="#alzheimer.Evaluation_Strategies_to_Ident">evaluation strategy</a> to identify the genetic cause of AD in a proband (when possible);</p></dd></dl><dl class="bkr_refwrap"><dt>4.</dt><dd><p class="no_top_margin">Inform <a href="#alzheimer.Inform_Genetic_Counseling_of_F">genetic counseling</a> of family members of an individual with AD.</p></dd></dl></dl>
</div><div id="alzheimer.Clinical_Characteristics_of_Al"><h2 id="_alzheimer_Clinical_Characteristics_of_Al_">1. Clinical Characteristics of Alzheimer Disease</h2><p>Alzheimer disease (AD) is characterized by dementia that typically begins with subtle and poorly recognized failure of memory (often called mild cognitive impairment or MCI) and slowly becomes more severe and, eventually, incapacitating. Other common findings include confusion, poor judgment, language disturbance, visual complaints, agitation, withdrawal, and hallucinations. Occasionally, seizures, Parkinsonian features, increased muscle tone, myoclonus, incontinence, and mutism occur. Death usually results from general inanition, malnutrition, and pneumonia. The typical clinical duration of the disease is eight to ten years, with a range from one to 25 years.</p><p>Approximately 95% of all AD is late onset (age &#x0003e;60-65 years) and 5% is early onset (age &#x0003c;60-65 years).</p><p>Establishing the diagnosis of Alzheimer disease relies on clinical-neuropathologic assessment. Neuropathologic findings of &#x003b2;-amyloid plaques, intraneuronal neurofibrillary tangles (containing tau protein), and amyloid angiopathy remain the gold standard for diagnosis.</p><ul><li class="half_rhythm"><div>The plaques should stain positively with &#x003b2;-amyloid antibodies and negative for prion antibodies (which are diagnostic of <a href="/books/n/gene/prion/?report=reader">prion diseases</a>).</div></li><li class="half_rhythm"><div>The numbers of plaques and tangles must exceed those found in age-matched controls without dementia. Guidelines for the quantitative assessment of these changes exist [<a class="bibr" href="#alzheimer.REF.montine.2012.1" rid="alzheimer.REF.montine.2012.1">Montine et al 2012</a>].</div></li><li class="half_rhythm"><div>Aggregation of alpha-synuclein in the form of Lewy bodies may also be found in neurons in the amygdala; frequently there is accumulation of TDP-43 protein [<a class="bibr" href="#alzheimer.REF.james.2016.2983" rid="alzheimer.REF.james.2016.2983">James et al 2016</a>, <a class="bibr" href="#alzheimer.REF.lemstra.2017.113" rid="alzheimer.REF.lemstra.2017.113">Lemstra et al 2017</a>].</div></li></ul><p>The clinical diagnosis of AD, based on clinical signs of slowly progressive dementia and neuroimaging findings of gross cerebral cortical atrophy, is correct approximately 80%-90% of the time. Greater precision can be obtained by use of more sophisticated studies such as amyloid PET imaging, CSF concentrations of amyloid and tau, and (in the near future) tau PET imaging and plasma concentration of &#x003b2; amyloid [<a class="bibr" href="#alzheimer.REF.dubois.2014.614" rid="alzheimer.REF.dubois.2014.614">Dubois et al 2014</a>, <a class="bibr" href="#alzheimer.REF.gabelle.2015.672" rid="alzheimer.REF.gabelle.2015.672">Gabelle et al 2015</a>, <a class="bibr" href="#alzheimer.REF.sutphen.2015.1029" rid="alzheimer.REF.sutphen.2015.1029">Sutphen et al 2015</a>, <a class="bibr" href="#alzheimer.REF.mattsson.2018.e388" rid="alzheimer.REF.mattsson.2018.e388">Mattsson et al 2018</a>].</p><p><b>Differential diagnosis of Alzheimer disease</b> includes the following:</p><ul><li class="half_rhythm"><div><b>Treatable forms of cognitive decline</b> including depression, chronic drug intoxication, chronic CNS infection, thyroid disease, vitamin deficiencies (especially B<sub>12</sub> and thiamine), CNS angiitis, and normal-pressure hydrocephalus [<a class="bibr" href="#alzheimer.REF.bird.2008" rid="alzheimer.REF.bird.2008">Bird &#x00026; Miller 2008</a>]. CT and MRI can identify some of these other causes of dementia, including neoplasms, normal-pressure hydrocephalus, and cerebral vascular disease.</div></li><li class="half_rhythm"><div><b>Other degenerative disorders associated with dementia,</b> such as frontotemporal dementia (including frontotemporal dementia with parkinsonism-17; FTDP-17), Picks disease, <a href="/books/n/gene/parkinson-overview/?report=reader">Parkinson disease</a>, diffuse Lewy body disease (LBD), Creutzfeldt-Jakob disease, and <a href="/books/n/gene/cadasil/?report=reader">CADASIL</a> [<a class="bibr" href="#alzheimer.REF.loy.2014.828" rid="alzheimer.REF.loy.2014.828">Loy et al 2014</a>, <a class="bibr" href="#alzheimer.REF.ferrari.2018.615" rid="alzheimer.REF.ferrari.2018.615">Ferrari et al 2018</a>].</div></li></ul></div><div id="alzheimer.Causes_of_Alzheimer_Disease"><h2 id="_alzheimer_Causes_of_Alzheimer_Disease_">2. Causes of Alzheimer Disease</h2><div class="iconblock whole_rhythm clearfix ten_col table-wrap" id="figalzheimerTcausesofalzheimerdisease"><a href="/books/NBK1161/table/alzheimer.T.causes_of_alzheimer_disease/?report=objectonly" target="object" title="Table 1. " class="img_link icnblk_img" rid-ob="figobalzheimerTcausesofalzheimerdisease"><img class="small-thumb" src="/corehtml/pmc/css/bookshelf/2.26/img/table-icon.gif" alt="Table Icon" /></a><div class="icnblk_cntnt"><h4 id="alzheimer.T.causes_of_alzheimer_disease"><a href="/books/NBK1161/table/alzheimer.T.causes_of_alzheimer_disease/?report=objectonly" target="object" rid-ob="figobalzheimerTcausesofalzheimerdisease">Table 1. </a></h4><p class="float-caption no_bottom_margin">Causes of Alzheimer Disease </p></div></div><div id="alzheimer.Familial_Alzheimer_Disease"><h3>Familial Alzheimer Disease</h3><p>Approximately 25% of all AD is familial (i.e., &#x02265;3 persons in a family have AD) and 75% is nonfamilial (i.e., an individual with AD and no known family history of AD). Because familial AD and nonfamilial AD appear to have the same clinical and pathologic phenotypes, they can only be distinguished by family history and/or by molecular genetic testing.</p><div id="alzheimer.LateOnset_Familial_AD"><h4>Late-Onset Familial AD</h4><p>Investigations have supported the concept that late-onset AD (age &#x0003e;60-65 years) is a complex disorder that may involve multiple susceptibility genes [<a class="bibr" href="#alzheimer.REF.van_cauwenberghe.2016.421" rid="alzheimer.REF.van_cauwenberghe.2016.421">Van Cauwenberghe et al 2016</a>].</p><p>While the association of the <i>APOE</i> e4 allele with AD is significant, <i>APOE</i> genotyping is neither fully specific nor sensitive. While <i>APOE</i> genotyping may have an adjunct role in the diagnosis of AD in symptomatic individuals, it appears to have little role at this time in predictive testing of asymptomatic individuals. As reviewed and summarized by <a class="bibr" href="#alzheimer.REF.van_cauwenberghe.2016.421" rid="alzheimer.REF.van_cauwenberghe.2016.421">Van Cauwenberghe et al [2016]</a>, the gene <i>APOE</i> has three major allelic variants &#x02013; e2, e3, and e4 &#x02013; which encode different isoforms of the protein ApoE. The presence of the <i>APOE</i> e4 allele in the heterozygous state (<i>APOE</i> e3/e4) or the homozygous state (<i>APOE</i> e4/e4) increases the risk for early-onset and late-onset AD but is not sufficient to cause disease. Only 20%-25% of individuals in the general population are heterozygous or homozygous for the e4 allele compared to 20%-65% of individuals with AD. The risk effect is estimated to be threefold for heterozygotes (<i>APOE</i> e3/e4) and 15-fold for homozygotes (<i>APOE</i> e4/e4). Using data from community-based samples, <a class="bibr" href="#alzheimer.REF.qian.2017.e1002254" rid="alzheimer.REF.qian.2017.e1002254">Qian et al [2017]</a> determined that a heterozygote for an <i>APO</i> e4 allele has about a 10%-20% chance of developing AD by age 75, whereas an <i>APO</i> e4 homozygote has about a 25%-35% risk.</p><p>Approximately 42% of persons with AD do <b>not</b> have an <i>APOE</i> e4 allele. The absence of an <i>APOE</i> e4 allele does not rule out the diagnosis of AD.</p><p>Of note, the <i>APOE</i> e2 allele appears to have a protective effect [<a class="bibr" href="#alzheimer.REF.iacono.2015.14082" rid="alzheimer.REF.iacono.2015.14082">Iacono et al 2015</a>].</p></div><div id="alzheimer.Susceptibility_Genes"><h4>Susceptibility Genes</h4><p>Research studies have identified variants in ~20 genes that increase the risk of AD slightly (i.e., &#x0003c;2%). Many of these genes have a role in brain development, cytoskeletal organization, and immune function. Variants in these susceptibility genes differ from variants in genes known to cause Alzheimer disease as no variant in any of these genes "causes" AD; therefore, these genes should not be included in any diagnostic testing (see <a href="#alzheimer.Evaluation_Strategies_to_Ident">Evaluation Strategies</a>).</p><p>Furthermore, it should be noted that while various combinations of variants in these genes have been proposed as markers for genetic risk of developing AD (so-called "polygenic risk scores") [<a class="bibr" href="#alzheimer.REF.desikan.2017.e1002258" rid="alzheimer.REF.desikan.2017.e1002258">Desikan et al 2017</a>, <a class="bibr" href="#alzheimer.REF.tan.2017.484" rid="alzheimer.REF.tan.2017.484">Tan et al 2017</a>, <a class="bibr" href="#alzheimer.REF.tosto.2017.1180" rid="alzheimer.REF.tosto.2017.1180">Tosto et al 2017</a>], at present these risk scores are of no known clinical utility.</p><p>The following list of susceptibility genes is based on reviews by <a class="bibr" href="#alzheimer.REF.naj.2014.1394" rid="alzheimer.REF.naj.2014.1394">Naj et al [2014]</a>, <a class="bibr" href="#alzheimer.REF.delaguila.2015.49" rid="alzheimer.REF.delaguila.2015.49">Del-Aguila et al [2015]</a>, <a class="bibr" href="#alzheimer.REF.ridge.2016.200.e13" rid="alzheimer.REF.ridge.2016.200.e13">Ridge et al [2016]</a>, <a class="bibr" href="#alzheimer.REF.van_cauwenberghe.2016.421" rid="alzheimer.REF.van_cauwenberghe.2016.421">Van Cauwenberghe et al [2016]</a>, and <a class="bibr" href="#alzheimer.REF.yokoyama.2016.691" rid="alzheimer.REF.yokoyama.2016.691">Yokoyama et al [2016]</a>: <i>ABCA7</i>, <i>AKAP9</i>, <i>BIN1</i>, <i>CASS4</i>, <i>CD2AP</i>, <i>CD33</i>, <i>CLU</i>, <i>EPHA1</i>, <i>FERMT2</i>, <i>HLA-DRB5/DRB1</i>, <i>INPP5D</i>, <i>MEF2C</i>, <i>MS4A6A/MS4A4E</i>, <i>PICALM</i>, <i>PLD3</i>, <i>PTK2B</i>, <i>SORL1</i>, <i>TREM2</i> (see NOTE), and <i>UNC5C.</i></p><p>NOTE: The <i>TREM2</i> p.Arg47His variant is a statistically significant risk factor for late-onset AD [<a class="bibr" href="#alzheimer.REF.guerreiro.2013.117" rid="alzheimer.REF.guerreiro.2013.117">Guerreiro et al 2013</a>, <a class="bibr" href="#alzheimer.REF.jonsson.2013.107" rid="alzheimer.REF.jonsson.2013.107">Jonsson et al 2013</a>]. Although this variant in the heterozygous state is rare in the general population (0.5%-1%), it results in an odds ratio of about 3.0 for the occurrence of AD. In a large family, apparent interaction of this variant with the <i>APOE</i> e4 allele increased the risk for late-onset AD [<a class="bibr" href="#alzheimer.REF.korvatska.2015.920" rid="alzheimer.REF.korvatska.2015.920">Korvatska et al 2015</a>].</p><p>See <a href="/books/NBK1161/bin/alzheimer-Table2.pdf">Table 2</a> (pdf) for potential functional contribution to Alzheimer disease risk.</p></div><div id="alzheimer.EarlyOnset_Familial_AD"><h4>Early-Onset Familial AD</h4><p>Early-onset familial AD (EOFAD) refers to AD that occurs in multiple members of a family with a mean onset usually before age 65 years. The dementia phenotype is similar to that of late-onset AD, sometimes with a long prodrome [<a class="bibr" href="#alzheimer.REF.schellenberg.2012.305" rid="alzheimer.REF.schellenberg.2012.305">Schellenberg &#x00026; Montine 2012</a>]. The genes causative of EOFAD and associated ages of onset are summarized in <a href="/books/NBK1161/table/alzheimer.T.earlyonset_familial_alzheime/?report=objectonly" target="object" rid-ob="figobalzheimerTearlyonsetfamilialalzheime">Table 3</a>.</p><div class="iconblock whole_rhythm clearfix ten_col table-wrap" id="figalzheimerTearlyonsetfamilialalzheime"><a href="/books/NBK1161/table/alzheimer.T.earlyonset_familial_alzheime/?report=objectonly" target="object" title="Table 3. " class="img_link icnblk_img" rid-ob="figobalzheimerTearlyonsetfamilialalzheime"><img class="small-thumb" src="/corehtml/pmc/css/bookshelf/2.26/img/table-icon.gif" alt="Table Icon" /></a><div class="icnblk_cntnt"><h4 id="alzheimer.T.earlyonset_familial_alzheime"><a href="/books/NBK1161/table/alzheimer.T.earlyonset_familial_alzheime/?report=objectonly" target="object" rid-ob="figobalzheimerTearlyonsetfamilialalzheime">Table 3. </a></h4><p class="float-caption no_bottom_margin">Early-Onset Familial Alzheimer Disease (EOFAD) </p></div></div></div></div></div><div id="alzheimer.Evaluation_Strategies_to_Ident"><h2 id="_alzheimer_Evaluation_Strategies_to_Ident_">3. Evaluation Strategies to Identify the Genetic Cause of Alzheimer Disease in a Proband</h2><p>Establishing a specific genetic cause of Alzheimer disease (AD):</p><ul><li class="half_rhythm"><div>Can aid in discussions of prognosis (which are beyond the scope of this <i>GeneReview</i>) and genetic counseling (<a href="#alzheimer.Inform_Genetic_Counseling_of_F">Section 4</a>);</div></li><li class="half_rhythm"><div>Usually involves a medical history, physical examination, and laboratory testing to exclude disorders included in the differential diagnosis (see <a href="#alzheimer.Clinical_Characteristics_of_Al">Section 1</a>), family history, and genomic/genetic testing.</div></li></ul><p>The two most important indicators of a genetic form of AD are age of onset (<a href="/books/NBK1161/table/alzheimer.T.earlyonset_familial_alzheime/?report=objectonly" target="object" rid-ob="figobalzheimerTearlyonsetfamilialalzheime">Table 3</a>) and positive family history of dementia.</p><ul><li class="half_rhythm"><div>There is no specific age cutoff and the general rule is that in a single individual diagnosed with AD, the earlier the onset, the more likely a genetic cause. Onset before 50 years has the highest likelihood of a genetic cause and after 70 years the lowest.</div></li><li class="half_rhythm"><div>A positive family history (&#x02265;3 affected persons) of early-onset dementia increases the probability of a genetic cause.</div></li></ul><p><b>Family history.</b> A three-generation family history should be taken, with attention to relatives with manifestations of AD and documentation of relevant findings through direct examination or review of medical records, including results of molecular genetic testing.</p><p><b>Molecular genetic testing approaches</b> can include a combination of gene-targeted testing (multigene panel) and comprehensive genomic testing (exome sequencing or genome sequencing). Gene-targeted testing requires the clinician to hypothesize which gene(s) are likely involved, whereas genomic testing does not.</p><p>Because of the significant overlap in clinical manifestations and age of onset in AD, single-gene testing (i.e., sequence analysis, followed by gene-targeted deletion/duplication analysis) is rarely useful and typically NOT recommended.</p><p><b>A multigene panel</b> (see NOTE) that includes <i>APOE</i> (specifically for detection and interpretation of the e4 allele) and all three genes listed in <a href="/books/NBK1161/table/alzheimer.T.earlyonset_familial_alzheime/?report=objectonly" target="object" rid-ob="figobalzheimerTearlyonsetfamilialalzheime">Table 3</a> is most likely to identify the genetic cause of the condition while limiting identification of variants of uncertain significance and pathogenic variants in genes that do not explain the underlying phenotype. Note: (1) The genes included in the panel and the diagnostic sensitivity of the testing used for each gene vary by laboratory and are likely to change over time. (2) Some multigene panels may include genes not associated with the condition discussed in this <i>GeneReview</i>. (3) In some laboratories, panel options may include a custom laboratory-designed panel and/or custom phenotype-focused exome analysis that includes genes specified by the clinician. (4) Methods used in a panel may include sequence analysis, deletion/duplication analysis, and/or other non-sequencing-based tests. (5) Because Alzheimer disease susceptibility genes (<a href="/books/NBK1161/bin/alzheimer-Table2.pdf">Table 2</a>) are not "causative," they should not be included in a multigene panel.</p><p>NOTE: Some laboratories offer multigene panels for "neurodegenerative disorders." While the genes included in such panels are likely to vary significantly by laboratory, often the genes known to cause the disorders mentioned in the differential diagnosis of AD (see <a href="#alzheimer.Clinical_Characteristics_of_Al">Section 1</a>), such as Parkinson disease, FTD, ALS, and prion-related disorders, are included. Because the clinical diagnosis of AD is usually "possible" or "probable" rather than "definite," it frequently is reasonable to use such a multigene panel.</p><p>For an introduction to multigene panels click <a href="/books/n/gene/app5/?report=reader#app5.Multigene_Panels">here</a>. More detailed information for clinicians ordering genetic tests can be found <a href="/books/n/gene/app5/?report=reader#app5.Multigene_Panels_FAQs">here</a>.</p><p><b>Comprehensive genomic testing</b> (which does not require the clinician to determine which gene[s] are likely involved) may be considered if a multigene panel does not identify a cause for the findings that prompted testing. <b>Exome sequencing</b> is most commonly used; <b>genome sequencing</b> is also possible. If exome sequencing is not diagnostic, <b>exome array</b> (when clinically available) may be considered to detect (multi)exon deletions or duplications that cannot be detected by sequence analysis.</p><p>For an introduction to comprehensive genomic testing click <a href="/books/n/gene/app5/?report=reader#app5.Comprehensive_Genomic_Testing">here</a>. More detailed information for clinicians ordering genomic testing can be found <a href="/books/n/gene/app5/?report=reader#app5.Comprehensive_Genomic_Testing_1">here</a>.</p></div><div id="alzheimer.Inform_Genetic_Counseling_of_F"><h2 id="_alzheimer_Inform_Genetic_Counseling_of_F_">4. Inform Genetic Counseling of Family Members of an Individual with Alzheimer Disease</h2><p>
<i>Genetic counseling is the process of providing individuals and families with
information on the nature, mode(s) of inheritance, and implications of genetic disorders to help them
make informed medical and personal decisions. The following section deals with genetic
risk assessment and the use of family history and genetic testing to clarify genetic
status for family members; it is not meant to address all personal, cultural, or
ethical issues that may arise or to substitute for consultation with a genetics
professional</i>. &#x02014;ED.</p><div id="alzheimer.Risk_to_Family_Members__Nonfam"><h3>Risk to Family Members &#x02013; Nonfamilial Alzheimer Disease</h3><p>Genetic counseling for people with late-onset nonfamilial AD (i.e., an individual with AD and no known family history) and their family members must be empiric and relatively nonspecific. First-degree relatives of a person with nonfamilial AD have a cumulative lifetime risk of developing AD of approximately 15%-39%, which is typically reported as a 20%-25% risk [<a class="bibr" href="#alzheimer.REF.farrer.1989.485" rid="alzheimer.REF.farrer.1989.485">Farrer et al 1989</a>, <a class="bibr" href="#alzheimer.REF.silverman.1994.577" rid="alzheimer.REF.silverman.1994.577">Silverman et al 1994</a>, <a class="bibr" href="#alzheimer.REF.lautenschlager.1996.641" rid="alzheimer.REF.lautenschlager.1996.641">Lautenschlager et al 1996</a>]. This risk is approximately two to three times that of the background risk (~27% vs 10.4%) [<a class="bibr" href="#alzheimer.REF.cupples.2004.192" rid="alzheimer.REF.cupples.2004.192">Cupples et al 2004</a>].</p><p>Disagreement exists as to whether the age of onset of AD in a person with nonfamilial AD changes the risk to first-degree relatives. <a class="bibr" href="#alzheimer.REF.silverman.2005.565" rid="alzheimer.REF.silverman.2005.565">Silverman et al [2005]</a> found that the risk to relatives of a proband with nonfamilial AD decreases with increasing age of onset of the proband.</p></div><div id="alzheimer.Risk_to_Family_Members__LateOn"><h3>Risk to Family Members &#x02013; Late-Onset Familial Alzheimer Disease (LOFAD)</h3><p>Inheritance of LOFAD (i.e., &#x02265;3 persons in a family have AD) is thought to be multifactorial and potentially involve multiple susceptibility genes [<a class="bibr" href="#alzheimer.REF.van_cauwenberghe.2016.421" rid="alzheimer.REF.van_cauwenberghe.2016.421">Van Cauwenberghe et al 2016</a>]. First-degree relatives of a person with LOFAD have a cumulative lifetime risk of developing AD of ~15%-25%, which is ~1.5-2 times the risk of the general population. When both parents have AD (i.e., conjugal AD) risk to their children is at least twice that of the general population risk [<a class="bibr" href="#alzheimer.REF.jayadev.2008.373" rid="alzheimer.REF.jayadev.2008.373">Jayadev et al 2008</a>].</p></div><div id="alzheimer.Risk_to_Family_Members__APP_PS"><h3>Risk to Family Members &#x02013; <i>APP-</i>, <i>PSEN1-</i>, or <i>PSEN2-</i>Related Early-Onset Familial Alzheimer Disease (EOFAD)</h3><p>EOFAD in which an individual has a pathogenic variant in <i>APP</i>, <i>PSEN1</i>, or <i>PSEN2</i> represents an autosomal dominant disease. This section refers only to families having a known EOFAD-causing <i>APP</i>, <i>PSEN1</i>, or <i>PSEN2</i> pathogenic variant. Guidelines for counseling these families have been published [<a class="bibr" href="#alzheimer.REF.goldman.2011.597" rid="alzheimer.REF.goldman.2011.597">Goldman et al 2011</a>].</p><p>
<b>Parents of a proband</b>
</p><ul><li class="half_rhythm"><div>Most individuals diagnosed as having <i>APP-</i>, <i>PSEN1-</i>, or <i>PSEN2</i>-related EOFAD have had an affected parent.</div><ul><li class="half_rhythm"><div>Because the onset of EOFAD is typically in early adulthood and the progression is rapid, affected parents are not alive at the time of diagnosis of their children.</div></li><li class="half_rhythm"><div>Occasionally, neither parent is identified as having had AD, but a second-degree relative (e.g., an uncle, aunt, and/or grandparent) has or had EOFAD. In this instance, a parent of the proband is presumed to be heterozygous for a familial AD-causing pathogenic variant associated with reduced (age-related) penetrance.</div></li></ul></li><li class="half_rhythm"><div>A proband with EOFAD may have the disorder as the result of a <i>de novo</i> pathogenic variant, although this has not been documented.</div></li><li class="half_rhythm"><div>The family history of some individuals diagnosed with EOFAD may appear to be negative because of failure to recognize the disorder in family members, early death of the parent before the onset of symptoms, or reduced (age-related) penetrance. Therefore, an apparently negative family history cannot be considered confirmed unless appropriate clinical evaluation and/or molecular genetic testing has been performed on the parents of the proband.</div></li></ul><p><b>Sibs of a proband.</b> The risk to sibs depends on the clinical/genetic status of the parents:</p><ul><li class="half_rhythm"><div>If a parent of the proband was affected and/or is known to be heterozygous for an <i>APP-</i>, <i>PSEN1-</i>, or <i>PSEN2</i>-related EOFAD pathogenic variant, the risk to sibs of having inherited the variant is 50%.</div></li><li class="half_rhythm"><div>Sibs of a proband with clinically unaffected parents are still presumed to be at increased risk for EOFAD because of the possibility of reduced (age-related) penetrance in a parent.</div></li></ul><p><b>Offspring of a proband.</b> Each child of an individual with <i>APP-</i>, <i>PSEN1-</i>, or <i>PSEN2</i>-related EOFAD has a 50% chance of inheriting the EOFAD-causing pathogenic variant.</p><p><b>Other family members.</b> The risk to other family members depends on the status of the proband's parents: if a parent has the pathogenic variant, the parent's family members may be at risk.</p></div><div id="alzheimer.Related_Genetic_Counseling_Iss"><h3>Related Genetic Counseling Issues</h3><p>
<b>Predictive testing for <i>APP-</i>, <i>PSEN1-</i>, or <i>PSEN2</i>-related EOFAD (i.e., testing of asymptomatic at-risk individuals)</b>
</p><ul><li class="half_rhythm"><div>Predictive testing for asymptomatic adults at risk for <i>APP-</i>, <i>PSEN1-</i>, or <i>PSEN2</i>-related EOFAD is possible if the pathogenic variant has been identified in an affected family member. It should be remembered that testing of asymptomatic at-risk individuals with nonspecific or equivocal symptoms is predictive testing, not diagnostic testing.</div></li><li class="half_rhythm"><div>Potential consequences of such testing (including, but not limited to, socioeconomic changes and the need for long-term follow up and evaluation arrangements for individuals with a positive test result) as well as the capabilities and limitations of predictive testing should be discussed in the context of formal genetic counseling prior to testing.</div></li></ul><p><b>Predictive testing for <i>APP-</i>, <i>PSEN1-</i>, or <i>PSEN2</i>-related</b>
<b>EOFAD in minors (i.e., testing of asymptomatic at-risk individuals younger than age 18 years)</b></p><ul><li class="half_rhythm"><div>For asymptomatic minors at risk for adult-onset conditions for which early treatment would have no beneficial effect on disease morbidity and mortality, predictive genetic testing is considered inappropriate, primarily because it negates the autonomy of the child with no compelling benefit. Further, concern exists regarding the potential unhealthy adverse effects that such information may have on family dynamics, the risk of discrimination and stigmatization in the future, and the anxiety that such information may cause.</div></li><li class="half_rhythm"><div>For more information, see the National Society of Genetic Counselors <a href="https://www.nsgc.org/Policy-Research-and-Publications/Position-Statements/Position-Statements/Post/genetic-testing-of-minors-for-adult-onset-conditions" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">position statement</a> on genetic testing of minors for adult-onset conditions and the American Academy of Pediatrics and American College of Medical Genetics and Genomics <a href="https://pediatrics.aappublications.org/content/131/3/620.full.pdf" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">policy statement</a>: ethical and policy issues in genetic testing and screening of children.</div></li></ul><p>In a family with an established diagnosis of EOFAD, it is appropriate to consider testing of symptomatic individuals regardless of age.</p><p><b><i>APOE</i> genotyping.</b> At this time, it is generally agreed that <i>APOE</i> genotyping has little role in predictive testing. The presence of one or two copies of the <i>APOE</i> e4 allele increases the lifetime risk of AD in an asymptomatic individual but does not constitute a diagnosis of AD (i.e., an individual may have one or two copies of the <i>APOE</i> e4 allele and never develop AD). Likewise, absence of one or two copies of the <i>APOE</i> e4 allele does not eliminate the risk for AD in an asymptomatic individual (~42% of persons with AD do not have an <i>APOE</i> e4 allele).</p><ul><li class="half_rhythm"><div>
<b><i>APOE</i> e4/e4</b>
</div><ul><li class="half_rhythm"><div>A young asymptomatic female who is homozygous for the <i>APOE</i> e4 allele has a 40%-45% probability of developing AD by age 75 years, compared with 10%-15% probability in the general female population.</div></li><li class="half_rhythm"><div>A young asymptomatic homozygous male has a 25%-30% risk of developing AD by age 80 years, compared with 10%-15% probability in the general male population [<a class="bibr" href="#alzheimer.REF.breitner.1999.321" rid="alzheimer.REF.breitner.1999.321">Breitner et al 1999</a>, <a class="bibr" href="#alzheimer.REF.qian.2017.e1002254" rid="alzheimer.REF.qian.2017.e1002254">Qian et al 2017</a>, <a class="bibr" href="#alzheimer.REF.liu.2018.602" rid="alzheimer.REF.liu.2018.602">Liu &#x00026; Caselli 2018</a>].</div></li></ul></li><li class="half_rhythm"><div><b><i>APOE</i> e3/e4.</b> For an asymptomatic person heterozygous for an <i>APOE</i> e4 allele, the lifetime risk of developing AD is lower (15%-25%) and the likely age of onset is later (peak age 80s) [<a class="bibr" href="#alzheimer.REF.breitner.1999.321" rid="alzheimer.REF.breitner.1999.321">Breitner et al 1999</a>, <a class="bibr" href="#alzheimer.REF.neu.2017.1178" rid="alzheimer.REF.neu.2017.1178">Neu et al 2017</a>, <a class="bibr" href="#alzheimer.REF.qian.2017.e1002254" rid="alzheimer.REF.qian.2017.e1002254">Qian et al 2017</a>].</div></li></ul><p>See the <a href="https://alzfdn.org/genetesting/" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">Statement of The Alzheimer's Foundation of America (AFA) and AFA's Medical, Scientific and Memory Screening Advisory Board on Genetic Testing to Determine Risk of Alzheimer's Disease</a> and <a class="bibr" href="#alzheimer.REF.frank.2018.421" rid="alzheimer.REF.frank.2018.421">Frank et al [2018]</a> for further discussion of predictive testing for AD.</p></div></div><div id="alzheimer.Resources"><h2 id="_alzheimer_Resources_">Resources</h2><p>
<i>GeneReviews staff has selected the following disease-specific and/or umbrella
support organizations and/or registries for the benefit of individuals with this disorder
and their families. GeneReviews is not responsible for the information provided by other
organizations. For information on selection criteria, click <a href="/books/n/gene/app4/?report=reader">here</a>.</i></p>
<ul><li class="half_rhythm"><div>
<b>Alzheimer's Association</b>
</div><div>225 North Michigan Avenue</div><div>Fl 17</div><div>Chicago IL 60601-7633</div><div><b>Phone:</b> 800-272-3900 (Toll-free 24/7 Helpline); 866-403-3073 (Toll-free 24/7 Helpline - TDD); 312-335-8700</div><div><b>Fax:</b> 866-335-5886 (toll-free)</div><div><b>Email:</b> info@alz.org</div><div>
<a href="http://www.alz.org" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">www.alz.org</a>
</div></li><li class="half_rhythm"><div>
<b>Alzheimer's Disease Education and Referral Center (ADEAR)</b>
</div><div>PO Box 8250</div><div>Silver Spring MD 20907</div><div><b>Phone:</b> 800-438-4380 (toll-free)</div><div><b>Fax:</b> 301-495-3334</div><div><b>Email:</b> adear@alzheimers.org</div><div>
<a href="http://www.nia.nih.gov/alzheimers" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">www.nia.nih.gov/alzheimers</a>
</div></li><li class="half_rhythm"><div>
<b>National Library of Medicine Genetics Home Reference</b>
</div><div>
<a href="https://ghr.nlm.nih.gov/condition/alzheimer-disease" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">Alzheimer Disease</a>
</div></li><li class="half_rhythm"><div>
<b>NCBI Genes and Disease</b>
</div><div>
<a href="/books/NBK22170/" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">Alzheimer Disease</a>
</div></li><li class="half_rhythm"><div>
<b>National Institute on Aging</b>
</div><div>31 Center Drive</div><div>Building 31, Room 5C27</div><div>MSC 2292</div><div>Bethesda MD 20892</div><div><b>Phone:</b> 301-496-1752; 800-222-2225 (toll-free); 800-222-4225 (toll-free TTY)</div><div><b>Fax:</b> 301-496-1072</div><div>
<a href="http://www.nia.nih.gov" ref="pagearea=body&amp;targetsite=external&amp;targetcat=link&amp;targettype=uri">www.nia.nih.gov</a>
</div></li></ul>
</div><div id="alzheimer.Chapter_Notes"><h2 id="_alzheimer_Chapter_Notes_">Chapter Notes</h2><div id="alzheimer.Revision_History"><h3>Revision History</h3><ul><li class="half_rhythm"><div>20 December 2018 (bp) Comprehensive update posted live</div></li><li class="half_rhythm"><div>30 March 2010 (me) Comprehensive update posted live</div></li><li class="half_rhythm"><div>9 May 2007 (me) Comprehensive update posted live</div></li><li class="half_rhythm"><div>10 February 2005 (me) Comprehensive update posted live</div></li><li class="half_rhythm"><div>29 January 2003 (me) Comprehensive update posted live</div></li><li class="half_rhythm"><div>23 October 1998 (me) Overview posted live</div></li><li class="half_rhythm"><div>Spring 1996 (tb) Original submission</div></li></ul></div></div><div id="alzheimer.References"><h2 id="_alzheimer_References_">References</h2><div id="alzheimer.Literature_Cited"><h3>Literature Cited</h3><ul class="simple-list"><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.bird.2008">Bird TD, Miller BL. Alzheimer's disease and primary dementias. In: Fauci AS, Braunwald E, Kasper DL, Hauser SL, Longo DL, Jameson JL, Loscalzo J, eds. <em>Harrison's Principles of Internal Medicine.</em> 17 ed. New York, NY: McGraw-Hill; 2008:2393-406.</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.breitner.1999.321">Breitner
JC, Wyse
BW, Anthony
JC, Welsh-Bohmer
KA, Steffens
DC, Norton
MC, Tschanz
JT, Plassman
BL, Meyer
MR, Skoog
I, Khachaturian
A. APOE-epsilon4 count predicts age when prevalence of AD increases, then declines: the Cache County Study.
Neurology.
1999;53:321-31
[<a href="https://pubmed.ncbi.nlm.nih.gov/10430421" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 10430421</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.cupples.2004.192">Cupples
LA, Farrer
LA, Sadovnick
AD, Relkin
N, Whitehouse
P, Green
RC. Estimating risk curves for first-degree relatives of patients with Alzheimer's disease: the REVEAL study.
Genet Med.
2004;6:192&#x02013;6.
[<a href="https://pubmed.ncbi.nlm.nih.gov/15266206" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 15266206</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.delaguila.2015.49">Del-Aguila
JL, Koboldt
DC, Black
K, Chasse
R, Norton
J, Wilson
RK, Cruchaga
C. Alzheimer's disease: rare variants with large effect sizes.
Curr Opin Genet Dev.
2015;33:49-55.
[<a href="https://pubmed.ncbi.nlm.nih.gov/26311074" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 26311074</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.desikan.2017.e1002258">Desikan
RS, Fan
CC, Wang
Y, Schork
AJ, Cabral
HJ, Cupples
LA, Thompson
WK, Besser
L, Kukull
WA, Holland
D, Chen
CH, Brewer
JB, Karow
DS, Kauppi
K, Witoelar
A, Karch
CM, Bonham
LW, Yokoyama
JS, Rosen
HJ, Miller
BL, Dillon
WP, Wilson
DM, Hess
CP, Pericak-Vance
M, Haines
JL, Farrer
LA, Mayeux
R, Hardy
J, Goate
AM, Hyman
BT, Schellenberg
GD, McEvoy
LK, Andreassen
OA, Dale
AM. Genetic assessment of age-associated Alzheimer disease risk: development and validation of a polygenic hazard score.
PLoS Med.
2017;14:e1002258.
[<a href="/pmc/articles/PMC5360219/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5360219</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/28323831" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 28323831</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.dubois.2014.614">Dubois
B, Feldman
HH, Jacova
C, Hampel
H, Molinuevo
JL, Blennow
K, DeKosky
ST, Gauthier
S, Selkoe
D, Bateman
R, Cappa
S, Crutch
S, Engelborghs
S, Frisoni
GB, Fox
NC, Galasko
D, Habert
MO, Jicha
GA, Nordberg
A, Pasquier
F, Rabinovici
G, Robert
P, Rowe
C, Salloway
S, Sarazin
M, Epelbaum
S, de Souza
LC, Vellas
B, Visser
PJ, Schneider
L, Stern
Y, Scheltens
P, Cummings
JL. Advancing research diagnostic criteria for Alzheimer's disease: the IWG-2 criteria.
Lancet Neurol.
2014;13:614-29.
[<a href="https://pubmed.ncbi.nlm.nih.gov/24849862" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 24849862</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.farrer.1989.485">Farrer
LA, O'Sullivan
DM, Cupples
LA, Growdon
JH, Myers
RH. Assessment of genetic risk for Alzheimer's disease among first-degree relatives.
Ann Neurol.
1989;25:485&#x02013;93
[<a href="https://pubmed.ncbi.nlm.nih.gov/2774490" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 2774490</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.ferrari.2018.615">Ferrari
C, Nacmias
B, Sorbi
S. The diagnosis of dementias: a practical tool not to miss rare causes.
Neurol Sci.
2018;39:615-27.
[<a href="https://pubmed.ncbi.nlm.nih.gov/29198043" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 29198043</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.frank.2018.421">Frank
L, Wesson Ashford
J, Bayley
PJ, Borson
S, Buschke
H, Cohen
D, Cummings
JL, Davies
P, Dean
M, Finkel
SI, Hyer
L, Perry
G, Powers
RE, Schmitt
F. Genetic risk of Alzheimer&#x02019;s disease: three wishes now that the genie is out of the bottle.
J Alzheimers Dis.
2018:66:421-3.
[<a href="/pmc/articles/PMC6218128/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC6218128</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/30282369" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 30282369</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.gabelle.2015.672">Gabelle
A, Schraen
S, Gutierrez
LA, Pays
C, Rouaud
O, Bu&#x000e9;e
L, Touchon
J, Helmer
C, Lambert
JC, Berr
C. Plasma &#x003b2;-amyloid 40 levels are positively associated with mortality risks in the elderly.
Alzheimers Dement.
2015;11:672-80
[<a href="https://pubmed.ncbi.nlm.nih.gov/25022539" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 25022539</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.goldman.2011.597">Goldman
JS, Hahn
SE, Catania
JW, LaRusse-Eckert
S, Butson
MB, Rumbaugh
M, Strecker
MN, Roberts
JS, Burke
W, Mayeux
R, Bird
T, et al.
Genetic counseling and testing for Alzheimer disease: joint practice guidelines of the American College of Medical Genetics and the National Society of Genetic Counselors.
Genet Med.
2011;13:597-605.
[<a href="/pmc/articles/PMC3326653/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC3326653</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/21577118" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 21577118</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.guerreiro.2013.117">Guerreiro
R, Wojtas
A, Bras
J, Carrasquillo
M, Rogaeva
E, Majounie
E, Cruchaga
C, Sassi
C, Kauwe
JS, Younkin
S, Hazrati
L, Collinge
J, Pocock
J, Lashley
T, Williams
J, Lambert
JC, Amouyel
P, Goate
A, Rademakers
R, Morgan
K, Powell
J, St George-Hyslop
P, Singleton
A, Hardy
J, et al.
TREM2 variants in Alzheimer's disease.
N Engl J Med.
2013;368:117&#x02013;27.
[<a href="/pmc/articles/PMC3631573/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC3631573</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/23150934" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 23150934</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.iacono.2015.14082">Iacono
D, Zandi
P, Gross
M, Markesbery
WR, Pletnikova
O, Rudow
G, Troncoso
JC. APO&#x003b5;2 and education in cognitively normal older subjects with high levels of AD pathology at autopsy: findings from the Nun Study.
Oncotarget.
2015;6:14082-91.
[<a href="/pmc/articles/PMC4546453/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4546453</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/26101858" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 26101858</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.james.2016.2983">James
BD, Wilson
RS, Boyle
PA, Trojanowski
JQ, Bennett
DA, Schneider
JA. TDP-43 stage, mixed pathologies, and clinical Alzheimer's-type dementia.
Brain.
2016;139:2983-93
[<a href="/pmc/articles/PMC5091047/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5091047</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/27694152" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 27694152</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.jayadev.2010.1143">Jayadev
S, Leverenz
JB, Steinbart
E, Stahl
J, Klunk
W, Yu
CE, Bird
TD. Alzheimer's disease phenotypes and genotypes associated with mutations in presenilin 2.
Brain.
2010;133:1143-54.
[<a href="/pmc/articles/PMC2850581/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC2850581</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/20375137" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 20375137</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.jayadev.2008.373">Jayadev
S, Steinbart
EJ, Chi
YY, Kukull
WA, Schellenberg
GD, Bird
TD. Conjugal Alzheimer disease: risk in children when both parents have Alzheimer disease.
Arch Neurol.
2008;65:373-8
[<a href="https://pubmed.ncbi.nlm.nih.gov/18332250" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 18332250</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.jonsson.2013.107">Jonsson
T, Stefansson
H, Ph
D SS, Jonsdottir
I, Jonsson
PV, Snaedal
J, Bjornsson
S, Huttenlocher
J, Levey
AI, Lah
JJ, Rujescu
D, Hampel
H, Giegling
I, Andreassen
OA, Engedal
K, Ulstein
I, Djurovic
S, Ibrahim-Verbaas
C, Hofman
A, Ikram
MA, van Duijn
CM, Thorsteinsdottir
U, Kong
A, Stefansson
K.
Variant of TREM2 associated with the risk of Alzheimer's disease.
N Engl J Med.
2013;368:107&#x02013;16.
[<a href="/pmc/articles/PMC3677583/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC3677583</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/23150908" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 23150908</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.korvatska.2015.920">Korvatska
O, Leverenz
JB, Jayadev
S, McMillan
P, Kurtz
I, Guo
X, Rumbaugh
M, Matsushita
M, Girirajan
S, Dorschner
MO, Kiianitsa
K, Yu
CE, Brkanac
Z, Garden
GA, Raskind
WH, Bird
TD. R47H variant of TREM2 associated with Alzheimer disease in a large late-onset family: clinical, genetic, and neuropathological study.
JAMA Neurol.
2015;72:920&#x02013;7.
[<a href="/pmc/articles/PMC4825672/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4825672</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/26076170" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 26076170</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.lalli.2014">Lalli MA, Cox HC, Arcila ML, Cadavid L, Moreno S, Garcia G, Madrigal L, Reiman EM, Arcos-Burgos M, Bedoya G, Brunkow ME, Glusman G, Roach JC, Hood L, Kosik KS, Lopera F. Origin of the PSEN1 E280A mutation causing early-onset Alzheimer's disease. Alzheimers Dement. 2014;10:S277-S283.e10. [<a href="/pmc/articles/PMC4019728/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4019728</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/24239249" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 24239249</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.larner.2013.653">Larner
AJ. Presenilin-1 mutations in Alzheimer's disease: an update on genotype-phenotype relationships.
J Alzheimers Dis.
2013;37:653-9.
[<a href="https://pubmed.ncbi.nlm.nih.gov/23948899" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 23948899</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.lautenschlager.1996.641">Lautenschlager
NT, Cupples
LA, Rao
VS, Auerbach
SA, Becker
R, Burke
J, Chui
H, Duara
R, Foley
EJ, Glatt
SL, Green
RC, Jones
R, Karlinsky
H, Kukull
WA, Kurz
A, Larson
EB, Martelli
K, Sadovnick
AD, Volicer
L, Waring
SC, Growdon
JH, Farrer
LA. Risk of dementia among relatives of Alzheimer's disease patients in the MIRAGE study: what is in store for the oldest old?
Neurology.
1996;46:641-50
[<a href="https://pubmed.ncbi.nlm.nih.gov/8618660" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 8618660</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.lee.2014.430">Lee
JH, Kahn
A, Cheng
R, Reitz
C, Vardarajan
B, Lantigua
R, Medrano
M, Jim&#x000e9;nez-Vel&#x000e1;zquez
IZ, Williamson
J, Nagy
P, Mayeux
R. Disease-related mutations among Caribbean Hispanics with familial dementia.
Mol Genet Genomic Med.
2014;2:430-7
[<a href="/pmc/articles/PMC4190878/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4190878</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/25333068" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 25333068</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.lemstra.2017.113">Lemstra
AW, de Beer
MH, Teunissen
CE, Schreuder
C, Scheltens
P, van der Flier
WM, Sikkes
SA. Concomitant AD pathology affects clinical manifestation and survival in dementia with Lewy bodies.
J Neurol Neurosurg Psychiatry.
2017;88:113-8.
[<a href="https://pubmed.ncbi.nlm.nih.gov/27794030" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 27794030</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.liu.2018.602">Liu
L, Caselli
RJ. Age stratification corrects bias in estimated hazard of APOE genotype for Alzheimer's disease.
Alzheimers Dement (N Y). 2018;4:602-8.
[<a href="/pmc/articles/PMC6226550/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC6226550</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/30450407" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 30450407</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.loy.2014.828">Loy
CT, Schofield
PR, Turner
AM, Kwok
JB. Genetics of dementia.
Lancet.
2014;383:828-40.
[<a href="https://pubmed.ncbi.nlm.nih.gov/23927914" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 23927914</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.mattsson.2018.e388">Mattsson
N, Smith
R, Strandberg
O, Palmqvist
S, Sch&#x000f6;ll
M, Insel
PS, H&#x000e4;gerstr&#x000f6;m
D, Ohlsson
T, Zetterberg
H, Blennow
K, J&#x000f6;gi
J, Hansson
O. Comparing 18F-AV-1451 with CSF t-tau and p-tau for diagnosis of Alzheimer disease.
Neurology.
2018;90:e388-e395.
[<a href="/pmc/articles/PMC5791788/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5791788</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/29321235" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 29321235</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.mccarron.2017.843">McCarron
M, McCallion
P, Reilly
E, Dunne
P, Carroll
R, Mulryan
N (2017) A prospective 20-year longitudinal follow-up of dementia in persons with Down syndrome.
J Intellect Disabil Res.
2017;61:843-52
[<a href="https://pubmed.ncbi.nlm.nih.gov/28664561" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 28664561</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.montine.2012.1">Montine
TJ, Phelps
CH, Beach
TG, Bigio
EH, Cairns
NJ, Dickson
DW, Duyckaerts
C, Frosch
MP, Masliah
E, Mirra
SS, Nelson
PT, Schneider
JA, Thal
DR, Trojanowski
JQ, Vinters
HV, Hyman
BT, et al.
National Institute on Aging-Alzheimer's Association guidelines for the neuropathologic assessment of Alzheimer's disease: a practical approach.
Acta Neuropathol.
2012;123:1-11.
[<a href="/pmc/articles/PMC3268003/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC3268003</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/22101365" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 22101365</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.naj.2014.1394">Naj
AC, Jun
G, Reitz
C, Kunkle
BW, Perry
W, Park
YS, Beecham
GW, Rajbhandary
RA, Hamilton-Nelson
KL, Wang
LS, Kauwe
JS, Huentelman
MJ, Myers
AJ, Bird
TD, Boeve
BF, Baldwin
CT, Jarvik
GP, Crane
PK, Rogaeva
E, Barmada
MM, Demirci
FY, Cruchaga
C, Kramer
PL, Ertekin-Taner
N, Hardy
J, Graff-Radford
NR, Green
RC, Larson
EB, St George-Hyslop
PH, Buxbaum
JD, Evans
DA, Schneider
JA, Lunetta
KL, Kamboh
MI, Saykin
AJ, Reiman
EM, De Jager
PL, Bennett
DA, Morris
JC, Montine
TJ, Goate
AM, Blacker
D, Tsuang
DW, Hakonarson
H, Kukull
WA, Foroud
TM, Martin
ER, Haines
JL, Mayeux
RP, et al.
Effects of multiple genetic loci on age at onset in late-onset Alzheimer disease: a genome-wide association study.
JAMA Neurol.
2014;71:1394-404.
[<a href="/pmc/articles/PMC4314944/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4314944</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/25199842" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 25199842</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.neu.2017.1178">Neu
SC, Pa
J, Kukull
W, Beekly
D, Kuzma
A, Gangadharan
P, Wang
LS, Romero
K, Arneric
SP, Redolfi
A, Orlandi
D, Frisoni
GB, Au
R, Devine
S, Auerbach
S, Espinosa
A, Boada
M, Ruiz
A, Johnson
SC, Koscik
R, Wang
JJ, Hsu
WC, Chen
YL, Toga
AW. Apolipoprotein E genotype and sex risk factors for Alzheimer disease: a meta-analysis.
JAMA Neurol.
2017;74:1178-89.
[<a href="/pmc/articles/PMC5759346/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5759346</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/28846757" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 28846757</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.pasanen.2018.827">Pasanen
P, Myllykangas
L, P&#x000f6;yh&#x000f6;nen
M, Kiviharju
A, Siitonen
M, Hardy
J, Bras
J, Paetau
A, Tienari
PJ, Guerreiro
R, Verkkoniemi-Ahola
A. Genetics of dementia in a Finnish cohort.
Eur J Hum Genet.
2018;26:827-37.
[<a href="/pmc/articles/PMC5974394/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5974394</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/29476165" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 29476165</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.pilotto.2013.689591">Pilotto
A, Padovani
A, Borroni
B. Clinical, biological, and imaging features of monogenic Alzheimer's disease.
Biomed Res Int.
2013;2013:689591.
[<a href="/pmc/articles/PMC3860086/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC3860086</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/24377094" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 24377094</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.qian.2017.e1002254">Qian
J, Wolters
FJ, Beiser
A, Haan
M, Ikram
MA, Karlawish
J, Langbaum
JB, Neuhaus
JM, Reiman
EM, Roberts
JS, Seshadri
S, Tariot
PN, Woods
BM, Betensky
RA, Blacker
D. APOE-related risk of mild cognitive impairment and dementia for prevention trials: an analysis of four cohorts.
PLoS Med.
2017;14:e1002254.
[<a href="/pmc/articles/PMC5360223/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5360223</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/28323826" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 28323826</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.ridge.2016.200.e13">Ridge
PG, Hoyt
KB, Boehme
K, Mukherjee
S, Crane
PK, Haines
JL, Mayeux
R, Farrer
LA, Pericak-Vance
MA, Schellenberg
GD, Kauwe
JSK, et al.
Assessment of the genetic variance of late-onset Alzheimer's disease.
Neurobiol Aging.
2016;41:200.e13-200.e20.
[<a href="/pmc/articles/PMC4948179/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4948179</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/27036079" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 27036079</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.ryman.2014.253">Ryman
DC, Acosta-Baena
N, Aisen
PS, Bird
T, Danek
A, Fox
NC, Goate
A, Frommelt
P, Ghetti
B, Langbaum
JB, Lopera
F, Martins
R, Masters
CL, Mayeux
RP, McDade
E, Moreno
S, Reiman
EM, Ringman
JM, Salloway
S, Schofield
PR, Sperling
R, Tariot
PN, Xiong
C, Morris
JC, Bateman
RJ, et al.
Symptom onset in autosomal dominant Alzheimer disease: a systematic review and meta-analysis.
Neurology.
2014;83:253-60
[<a href="/pmc/articles/PMC4117367/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4117367</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/24928124" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 24928124</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.schellenberg.2012.305">Schellenberg
GD, Montine
TJ. The genetics and neuropathology of Alzheimer's disease.
Acta Neuropathol.
2012;124:305-23.
[<a href="/pmc/articles/PMC3708460/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC3708460</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/22618995" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 22618995</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.silverman.2005.565">Silverman
JM, Ciresi
G, Smith
CJ, Marin
DB, Schnaider-Beeri
M. Variability of familial risk of Alzheimer disease across the late life span.
Arch Gen Psychiatry.
2005;62:565-73
[<a href="https://pubmed.ncbi.nlm.nih.gov/15867110" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 15867110</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.silverman.1994.577">Silverman
JM, Li
G, Zaccario
ML, Smith
CJ, Schmeidler
J, Mohs
RC, Davis
KL. Patterns of risk in first-degree relatives of patients with Alzheimer's disease.
Arch Gen Psychiatry.
1994;51:577&#x02013;86.
[<a href="https://pubmed.ncbi.nlm.nih.gov/8031231" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 8031231</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.sutphen.2015.1029">Sutphen
CL, Jasielec
MS, Shah
AR, Macy
EM, Xiong
C, Vlassenko
AG, Benzinger
TL, Stoops
EE, Vanderstichele
HM, Brix
B, Darby
HD, Vandijck
ML, Ladenson
JH, Morris
JC, Holtzman
DM, Fagan
AM. Longitudinal cerebrospinal fluid biomarker changes in preclinical Alzheimer disease during middle age.
JAMA Neurol.
2015;72:1029-42.
[<a href="/pmc/articles/PMC4570860/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4570860</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/26147946" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 26147946</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.tan.2017.484">Tan
CH, Hyman
BT, Tan
JJX, Hess
CP, Dillon
WP, Schellenberg
GD, Besser
LM, Kukull
WA, Kauppi
K, McEvoy
LK, Andreassen
OA, Dale
AM, Fan
CC, Desikan
RS. Polygenic hazard scores in preclinical Alzheimer disease.
Ann Neurol.
2017;82:484-8.
[<a href="/pmc/articles/PMC5758043/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5758043</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/28940650" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 28940650</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.tosto.2017.1180">Tosto
G, Bird
TD, Tsuang
D, Bennett
DA, Boeve
BF, Cruchaga
C, Faber
K, Foroud
TM, Farlow
M, Goate
AM, Bertlesen
S, Graff-Radford
NR, Medrano
M, Lantigua
R, Manly
J, Ottman
R, Rosenberg
R, Schaid
DJ, Schupf
N, Stern
Y, Sweet
RA, Mayeux
R. Polygenic risk scores in familial Alzheimer disease.
Neurology.
2017;88:1180-6.
[<a href="/pmc/articles/PMC5373783/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC5373783</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/28213371" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 28213371</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.van_cauwenberghe.2016.421">Van Cauwenberghe
C, Van Broeckhoven
C, Sleegers
K. The genetic landscape of Alzheimer disease: clinical implications and perspectives.
Genet Med.
2016;18:421-30.
[<a href="/pmc/articles/PMC4857183/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4857183</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/26312828" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 26312828</span></a>]</div></p></li><li class="half_rhythm"><p><div class="bk_ref" id="alzheimer.REF.yokoyama.2016.691">Yokoyama
JS, Wang
Y, Schork
AJ, Thompson
WK, Karch
CM, Cruchaga
C, McEvoy
LK, Witoelar
A, Chen
CH, Holland
D, Brewer
JB, Franke
A, Dillon
WP, Wilson
DM, Mukherjee
P, Hess
CP, Miller
Z, Bonham
LW, Shen
J, Rabinovici
GD, Rosen
HJ, Miller
BL, Hyman
BT, Schellenberg
GD, Karlsen
TH, Andreassen
OA, Dale
AM, Desikan
RS, et al.
Association between genetic traits for immune-mediated diseases and Alzheimer disease.
JAMA Neurol.
2016;73:691-7.
[<a href="/pmc/articles/PMC4905783/" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pmc">PMC free article<span class="bk_prnt">: PMC4905783</span></a>] [<a href="https://pubmed.ncbi.nlm.nih.gov/27088644" ref="pagearea=cite-ref&amp;targetsite=entrez&amp;targetcat=link&amp;targettype=pubmed">PubMed<span class="bk_prnt">: 27088644</span></a>]</div></p></li></ul></div></div><div id="bk_toc_contnr"></div></div></div><div class="fm-sec"><h2 id="_NBK1161_pubdet_">Publication Details</h2><h3>Author Information and Affiliations</h3><div class="contrib half_rhythm"><span itemprop="author">Thomas D Bird</span><div class="affiliation small">Seattle VA Medical Center<br />Departments of Neurology and Medicine<br />University of Washington<br />Seattle, Washington<div><span class="email-label">Email: </span><a href="mailto:dev@null" data-email="ude.wu@zornmot" class="oemail">ude.wu@zornmot</a></div></div></div><h3>Publication History</h3><p class="small">Initial Posting: <span itemprop="datePublished">October 23, 1998</span>; Last Update: <span itemprop="dateModified">December 20, 2018</span>.</p><h3>Copyright</h3><div><div class="half_rhythm"><a href="/books/about/copyright/">Copyright</a> &#x000a9; 1993-2025, University of Washington, Seattle. GeneReviews is
a registered trademark of the University of Washington, Seattle. All rights
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contact: <a href="mailto:dev@null" data-email="ude.wu@tssamda" class="oemail">ude.wu@tssamda</a>.</p></div></div><h3>Publisher</h3><p><a href="http://www.washington.edu" ref="pagearea=page-banner&amp;targetsite=external&amp;targetcat=link&amp;targettype=publisher">University of Washington, Seattle</a>, Seattle (WA)</p><h3>NLM Citation</h3><p>Bird TD. Alzheimer Disease Overview. 1998 Oct 23 [Updated 2018 Dec 20]. In: Adam MP, Feldman J, Mirzaa GM, et al., editors. GeneReviews&#x000ae; [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2025. <span class="bk_cite_avail"></span></p></div><div class="small-screen-prev"><a href="/books/n/gene/alstrom/?report=reader"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" preserveAspectRatio="none"><path d="M75,30 c-80,60 -80,0 0,60 c-30,-60 -30,0 0,-60"></path><text x="20" y="28" textLength="60" style="font-size:25px">Prev</text></svg></a></div><div class="small-screen-next"><a href="/books/n/gene/als-overview/?report=reader"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100" preserveAspectRatio="none"><path d="M25,30c80,60 80,0 0,60 c30,-60 30,0 0,-60"></path><text x="20" y="28" textLength="60" style="font-size:25px">Next</text></svg></a></div></article><article data-type="table-wrap" id="figobalzheimerTcausesofalzheimerdisease"><div id="alzheimer.T.causes_of_alzheimer_disease" class="table"><h3><span class="label">Table 1. </span></h3><div class="caption"><p>Causes of Alzheimer Disease</p></div><p class="large-table-link" style="display:none"><span class="right"><a href="/books/NBK1161/table/alzheimer.T.causes_of_alzheimer_disease/?report=objectonly" target="object">View in own window</a></span></p><div class="large_tbl" id="__alzheimer.T.causes_of_alzheimer_disease_lrgtbl__"><table class="no_bottom_margin"><thead><tr><th id="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_1" scope="col" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Cause</th><th id="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_2" scope="col" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">% of Cases</th></tr></thead><tbody><tr><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Late-onset familial&#x000a0;<sup>1</sup> (age &#x0003e;60-65 years)</td><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">15%-25%</td></tr><tr><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Early-onset familial&#x000a0;<sup>1</sup> (age &#x0003c;60-65 years)</td><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">&#x0003c;2%</td></tr><tr><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Down syndrome&#x000a0;<sup>2</sup></td><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">&#x0003c;1%</td></tr><tr><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Unknown (includes genetic/environment interactions)</td><td headers="hd_h_alzheimer.T.causes_of_alzheimer_disease_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">~75%</td></tr></tbody></table></div><div class="tblwrap-foot"><div><dl class="temp-labeled-list small"><dl class="bkr_refwrap"><dt>1. </dt><dd><div id="alzheimer.TF.1.1"><p class="no_margin">&#x02265;3 persons in a family with AD</p></div></dd></dl><dl class="bkr_refwrap"><dt>2. </dt><dd><div id="alzheimer.TF.1.2"><p class="no_margin">Essentially all persons with Down syndrome (trisomy 21) develop the neuropathologic hallmarks of AD after age 40 years [<a class="bibr" href="#alzheimer.REF.mccarron.2017.843" rid="alzheimer.REF.mccarron.2017.843">McCarron et al 2017</a>]. If carefully observed or tested, more than half of individuals with DS also show clinical evidence of cognitive decline. The presumed reason for this association is the lifelong overexpression of <i>APP</i> on chromosome 21 encoding the amyloid precursor protein and the resultant overproduction of &#x003b2;-amyloid in the brains of persons who are trisomic for this gene.</p></div></dd></dl></dl></div></div></div></article><article data-type="table-wrap" id="figobalzheimerTearlyonsetfamilialalzheime"><div id="alzheimer.T.earlyonset_familial_alzheime" class="table"><h3><span class="label">Table 3. </span></h3><div class="caption"><p>Early-Onset Familial Alzheimer Disease (EOFAD)</p></div><p class="large-table-link" style="display:none"><span class="right"><a href="/books/NBK1161/table/alzheimer.T.earlyonset_familial_alzheime/?report=objectonly" target="object">View in own window</a></span></p><div class="large_tbl" id="__alzheimer.T.earlyonset_familial_alzheime_lrgtbl__"><table class="no_bottom_margin"><thead><tr><th id="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_1" scope="col" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Gene&#x000a0;<sup>1</sup></th><th id="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_2" scope="col" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Proportion of EOFAD&#x000a0;<sup>2</sup></th><th id="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_3" scope="col" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Age of Onset (yrs)</th><th id="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_4" colspan="2" scope="colgroup" rowspan="1" style="text-align:left;vertical-align:middle;">Other</th></tr></thead><tbody><tr><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">
<i>APP</i>
</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">10%-15%</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_3" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Usually 40s &#x00026; 50s, occasionally 60s (range 30-65)&#x000a0;3</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_4" colspan="2" rowspan="1" style="text-align:left;vertical-align:middle;"></td></tr><tr><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">
<i>PSEN1</i>
</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">20%-70%</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_3" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Usually 40s or early 50s (range 30s-early 60s); onset after age 65 thought to be rare</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_4" colspan="2" rowspan="1" style="text-align:left;vertical-align:middle;"><ul><li class="half_rhythm"><div>Relatively rapid progression over 6-7 yrs is common.</div></li><li class="half_rhythm"><div>Often associated w/seizures, myoclonus, &#x00026; language deficits&#x000a0;<sup>4</sup></div></li><li class="half_rhythm"><div>Founder variants identified in residents of the state of Antioquia, Colombia&#x000a0;<sup>5</sup> &#x00026; in Caribbean Hispanics&#x000a0;<sup>6</sup></div></li></ul>
</td></tr><tr><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">
<i>PSEN2</i>
</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">~5%</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_3" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">40-75</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_4" colspan="2" rowspan="1" style="text-align:left;vertical-align:middle;"><ul><li class="half_rhythm"><div>Mean duration: 11 yrs</div></li><li class="half_rhythm"><div>Reduced penetrance (i.e., asymptomatic heterozygotes age &#x0003e;80 yrs) reported&#x000a0;<sup>7</sup></div></li><li class="half_rhythm"><div>Founder variant identified in the Volga German population</div></li></ul>
</td></tr><tr><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_1" scope="row" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">Unknown</td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_2" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">20%-40%&#x000a0;<sup>8</sup></td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_3 hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_4" colspan="2" rowspan="1" style="text-align:left;vertical-align:middle;"></td><td headers="hd_h_alzheimer.T.earlyonset_familial_alzheime_1_1_1_4" rowspan="1" colspan="1" style="text-align:left;vertical-align:middle;">No major new gene for EOFAD has been identified because of overlap in the clinical presentation of AD and FTD caused by pathogenic variants in <i>MAPT</i>, <i>GRN</i>, <i>C9orf72.</i></td></tr></tbody></table></div><div class="tblwrap-foot"><div><dl class="temp-labeled-list small"><dl class="bkr_refwrap"><dt></dt><dd><div><p class="no_margin">AD = Alzheimer disease; FTD = frontotemporal dementia</p></div></dd></dl><dl class="bkr_refwrap"><dt>1. </dt><dd><div id="alzheimer.TF.3.1"><p class="no_margin">Genes are in alphabetic order.</p></div></dd></dl><dl class="bkr_refwrap"><dt>2. </dt><dd><div id="alzheimer.TF.3.2"><p class="no_margin">
<a class="bibr" href="#alzheimer.REF.schellenberg.2012.305" rid="alzheimer.REF.schellenberg.2012.305">Schellenberg &#x00026; Montine [2012]</a>
</p></div></dd></dl><dl class="bkr_refwrap"><dt>3. </dt><dd><div id="alzheimer.TF.3.3"><p class="no_margin">
<a class="bibr" href="#alzheimer.REF.pilotto.2013.689591" rid="alzheimer.REF.pilotto.2013.689591">Pilotto et al [2013]</a>
</p></div></dd></dl><dl class="bkr_refwrap"><dt>4. </dt><dd><div id="alzheimer.TF.3.4"><p class="no_margin"><a class="bibr" href="#alzheimer.REF.larner.2013.653" rid="alzheimer.REF.larner.2013.653">Larner [2013]</a>, <a class="bibr" href="#alzheimer.REF.ryman.2014.253" rid="alzheimer.REF.ryman.2014.253">Ryman et al [2014]</a></p></div></dd></dl><dl class="bkr_refwrap"><dt>5. </dt><dd><div id="alzheimer.TF.3.5"><p class="no_margin">
<a class="bibr" href="#alzheimer.REF.lalli.2014" rid="alzheimer.REF.lalli.2014">Lalli et al [2014]</a>
</p></div></dd></dl><dl class="bkr_refwrap"><dt>6. </dt><dd><div id="alzheimer.TF.3.6"><p class="no_margin">
<a class="bibr" href="#alzheimer.REF.lee.2014.430" rid="alzheimer.REF.lee.2014.430">Lee et al [2014]</a>
</p></div></dd></dl><dl class="bkr_refwrap"><dt>7. </dt><dd><div id="alzheimer.TF.3.7"><p class="no_margin">
<a class="bibr" href="#alzheimer.REF.jayadev.2010.1143" rid="alzheimer.REF.jayadev.2010.1143">Jayadev et al [2010]</a>
</p></div></dd></dl><dl class="bkr_refwrap"><dt>8. </dt><dd><div id="alzheimer.TF.3.8"><p class="no_margin">It is likely that pathogenic variants in other genes causative of EOFAD will be identified because kindreds with autosomal dominant FAD with no known pathogenic variants in <i>PSEN1</i>, <i>PSEN2</i>, or <i>APP</i> have been described [<a class="bibr" href="#alzheimer.REF.pasanen.2018.827" rid="alzheimer.REF.pasanen.2018.827">Pasanen et al 2018</a>].</p></div></dd></dl></dl></div></div></div></article></div><div id="jr-scripts"><script src="/corehtml/pmc/jatsreader/ptpmc_3.22/js/libs.min.js"> </script><script src="/corehtml/pmc/jatsreader/ptpmc_3.22/js/jr.min.js"> </script><script type="text/javascript">if (typeof (jQuery) != 'undefined') { (function ($) { $(function () { var min = Math.ceil(1); var max = Math.floor(100000); var randomNum = Math.floor(Math.random() * (max - min)) + min; var surveyUrl = "/projects/Gene/portal/surveys/seqdbui-survey.js?rando=" + randomNum.toString(); $.getScript(surveyUrl, function () { try { ncbi.seqDbUISurvey.init(); } catch (err) { console.info(err); } }).fail(function (jqxhr, settings, exception) { console.info('Cannot load survey script', jqxhr); });; }); })(jQuery); };</script></div></div>
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