Osteoglophonic dysplasia (OGD) is characterized by multisuture craniosynostosis (including cloverleaf skull), distinctive craniofacial features (prominent forehead, proptosis, widely spaced eyes, low-set ears, midface retrusion, short nose, anteverted nares, prognathism, high palate, failure of tooth eruption, and gingival overgrowth), profound short stature with rhizomelia, and short, broad hands and feet. Radiographs show copper beaten appearance to skull, multiple cystic long bone lesions consistent with non-ossifying fibromas, irregular vertebral bodies, and osteopenia with increased risk of fractures.

Individuals with aromatic L-amino acid decarboxylase (AADC) deficiency typically have complex symptoms, including motor, behavioral, cognitive, and autonomic findings. Symptom onset is in early infancy, typically within the first six months of life. The most common initial symptoms are often nonspecific, and include feeding difficulties, hypotonia, and developmental delay. More specific symptoms include oculogyric crises (which occur in the vast majority of affected individuals, typically starting in infancy), movement disorders (especially dystonia), and autonomic dysfunction (excessive sweating, temperature instability, ptosis, nasal congestion, hypoglycemic episodes). Sleep disturbance is present in a majority of affected individuals and can include insomnia, hypersomnia, or both. Mood disturbance, including irritability and anxiety, are also common. Brain MRI is typically either normal or may demonstrate nonspecific abnormalities, such as mild diffuse cerebral atrophy or delayed myelination. Seizures are an uncommon finding, occurring in fewer than 5% of affected individuals.

Carnitine palmitoyltransferase II (CPT II) deficiency is a disorder of long-chain fatty-acid oxidation. The three clinical presentations are lethal neonatal form, severe infantile hepatocardiomuscular form, and myopathic form (which is usually mild and can manifest from infancy to adulthood). While the former two are severe multisystemic diseases characterized by liver failure with hypoketotic hypoglycemia, cardiomyopathy, seizures, and early death, the latter is characterized by exercise-induced muscle pain and weakness, sometimes associated with myoglobinuria. The myopathic form of CPT II deficiency is the most common disorder of lipid metabolism affecting skeletal muscle and the most frequent cause of hereditary myoglobinuria. Males are more likely to be affected than females.

Autosomal dominant craniometaphyseal dysplasia (designated AD-CMD in this review) is characterized by progressive diffuse hyperostosis of cranial bones evident clinically as wide nasal bridge, paranasal bossing, widely spaced eyes with an increase in bizygomatic width, and prominent mandible. Development of dentition may be delayed and teeth may fail to erupt as a result of hyperostosis and sclerosis of alveolar bone. Progressive thickening of craniofacial bones continues throughout life, often resulting in narrowing of the cranial foramina, including the foramen magnum. If untreated, compression of cranial nerves can lead to disabling conditions such as facial palsy, blindness, or deafness (conductive and/or sensorineural hearing loss). In individuals with typical uncomplicated AD-CMD life expectancy is normal; in those with severe AD-CMD life expectancy can be reduced as a result of compression of the foramen magnum.

Craniometaphyseal dysplasia is an osteochondrodysplasia characterized by hyperostosis and sclerosis of the craniofacial bones associated with abnormal modeling of the metaphyses. Sclerosis of the skull may lead to asymmetry of the mandible, as well as to cranial nerve compression, that may finally result in hearing loss and facial palsy (summary by Nurnberg et al., 1997). The delineation of separate autosomal dominant (CMDD; 123000) and autosomal recessive forms of CMD by Gorlin et al. (1969) was confirmed by reports that made it evident that the dominant form is relatively mild and comparatively common, whereas the recessive form is rare, severe, and possibly heterogeneous.

Any primary ciliary dyskinesia in which the cause of the disease is a mutation in the CCDC151 gene.

CILD36 is an X-linked recessive disorder characterized by chronic airway disease and recurrent sinopulmonary infections beginning in childhood and caused by defective ciliary function. Affected individuals also have infertility due to defective sperm flagella. About half of patients have laterality defects due to ciliary dysfunction at the embryonic node (summary by Paff et al., 2017). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Dopamine beta-hydroxylase (DBH) deficiency is characterized by lack of sympathetic noradrenergic function resulting in profound deficits in autonomic regulation of cardiovascular function (orthostatic hypotension) and other autonomic dysfunction (ptosis, nasal stuffiness, sleep difficulties, and impaired ejaculation in males). Although DBH deficiency is present from birth, the diagnosis is often not generally recognized until late childhood. In the perinatal period, DBH deficiency has been complicated by vomiting, dehydration, hypotension, hypothermia, and hypoglycemia requiring repeated hospitalization, and the diagnosis may be identified fortuitously in the neonatal period with investigation of hypoglycemia. Children may report reduced exercise capacity. By early adulthood, individuals have profound orthostatic hypotension, greatly reduced exercise tolerance, ptosis, and nasal stuffiness. Presyncopal symptoms include dizziness, blurred vision, dyspnea, nuchal discomfort, and chest pain; symptoms may worsen in hot environments or after heavy meals or alcohol ingestion. Some individuals have abnormal kidney function, joint laxity, hypotonia, high-arched palate, anemia, and/or hypoglycemia.

Retinitis pigmentosa-82 with or without situs inversus (RP82) is an autosomal recessive form of retinal degeneration characterized by initial loss of rod photoreceptors, resulting in impaired night vision followed by progressive visual field constriction as both rod and cone photoreceptors die. Some affected individuals have situs inversus (Davidson et al., 2013; Audo et al., 2017). Male patients with infertility due to reduced or absent sperm motility have been reported; female fertility appears to be unaffected (Moye et al., 2019).

Immunodeficiency-58 is an autosomal recessive primary immunologic disorder characterized by early-onset skin lesions, including eczematous dermatitis, infectious abscesses, and warts, recurrent respiratory infections or allergies, and chronic persistent infections with candida, Molluscum contagiosum, mycobacteria, EBV, bacteria, and viruses. Some patients may have gastrointestinal involvement, including inflammatory bowel disease, EBV+ smooth muscle tumors, and esophagitis. Immunologic analysis shows defective T-cell function with decreased Treg cells and deficient CD3/CD28 costimulation responses in both CD4+ and CD8+ T cells. B-cell function may also be impaired (summary by Wang et al., 2016 and Alazami et al., 2018).

Immunodeficiency-97 with autoinflammation (IMD97) is an autosomal recessive complex immunologic disorder with variable features. Affected individuals present in the first decade of life with inflammatory interstitial lung disease or colitis due to abnormal tissue infiltration by activated T cells. Patients develop autoimmune cytopenias and may have lymphadenopathy; 1 reported patient had features of hemophagocytic lymphohistiocytosis (HLH; see FHL1, 267700). Some patients may have recurrent infections associated with mild lymphopenia, hypogammaglobulinemia, and NK cell dysfunction. Immunologic workup indicates signs of significant immune dysregulation with elevation of inflammatory serum markers, variable immune cell defects involving neutrophils, NK cells, and myeloid cells, and disrupted levels of T regulatory cells (Tregs). Two unrelated patients have been reported (summary by Takeda et al., 2019 and Thian et al., 2020).