Alternative titles; symbols
HGNC Approved Gene Symbol: BMPR1A
SNOMEDCT: 9273005;
Cytogenetic location: 10q23.2 Genomic coordinates (GRCh38) : 10:86,755,763-86,932,844 (from NCBI)
| Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
|---|---|---|---|---|
| 10q23.2 | Polyposis syndrome, hereditary mixed, 2 | 610069 | 3 | |
| Polyposis, juvenile intestinal | 174900 | Autosomal dominant | 3 |
See ACVRL1 (601284). Human cDNA clones encoding 4 putative transmembrane ser/thr kinases were identified by ten Dijke et al. (1993). Using degenerate DNA primers based on the human activin receptor type II (see 102581) and C. elegans Daf-1 gene products, they PCR-amplified mRNA from human erythroleukemia (HEL) cells, a cell type known to respond both to activin (147290) and TGF-beta (190180). The ALK3 gene encodes a 532-amino acid polypeptide that shares similar sequence and domain structures with the other 3 ALK genes they cloned. ALK1, ALK2 (102576), ALK3, and ALK4 (601300) share approximately 40% sequence identity with activin receptors type II and IIB, TGF-beta receptor (see 190181), and Daf-1 in their kinase domains but share 60 to 79% sequence identity among themselves, suggesting to ten Dijke et al. (1993) that the ALK gene products form a subfamily of receptor ser/thr kinases. By Northern analysis, ten Dijke et al. (1993) showed that ALK3 was expressed almost exclusively in human skeletal muscle with weak expression in heart and placenta.
Eng (2001) pointed out that the TGF-beta/BMP superfamily of molecules has been shown to be defective not only in neoplasia but also in the noncancer developmental syndromes primary pulmonary hypertension (178600) and hereditary hemorrhagic telangiectasia (HHT1, 187300; HHT2, 600376).
Elimination of the developing female reproductive tract in male fetuses is an essential step in mammalian sexual differentiation. In males, the fetal testis produces anti-mullerian hormone (AMH; 600957), which causes regression of the mullerian ducts, the primordia of the oviducts, uterus, and upper vagina. AMH induces regression by binding to a specific type II receptor (AMHR2; 600956). Mutations in AMH or AMHR2 in humans and mice disrupt signaling, producing male pseudohermaphrodites that possess oviducts and uteri. Jamin et al. (2002) showed that targeted disruption of the BMPR1A receptor protein in the mesenchymal cells of the mullerian ducts leads to retention of oviducts and uteri in males. These results identified BMPR1A as a type I receptor for AMH-induced regression of mullerian ducts. Because BMPR1A is evolutionarily conserved, these findings indicate that a component of the bone morphogenetic protein signaling pathway has been co-opted during evolution for male sexual development in amniotes.
In humans, mutations in the BMPR1A, SMAD4 (600993), and PTEN (601728) genes are responsible for juvenile polyposis syndrome, juvenile intestinal polyposis, and Cowden disease (CD; 158350), respectively. The development of polyposis is a common feature of these disorders, suggesting that there is an association between the BMP and PTEN pathways. To determine the mechanistic link between the 2 pathways and the related etiology of juvenile polyposis, He et al. (2004) generated mice in which Bmpr1a was conditionally inactivated; the conditional inactivation disturbed homeostasis of intestinal epithelial regeneration with an expansion of the stem and progenitor cell populations, eventually leading to intestinal polyposis resembling human juvenile polyposis syndrome. He et al. (2004) showed that BMP signaling suppresses Wnt signaling to ensure a balanced control stem cell self-renewal. Mechanistically, PTEN, through phosphatidylinositol-3 kinase/Akt, mediates the convergence of the BMP and Wnt pathways on control of beta-catenin (CTNNB1; 116806). The authors concluded that BMP signaling may control the duplication of intestinal stem cells, thereby preventing crypt fission and the subsequent increase in crypt number.
Waite and Eng (2003) searched for a link between PTEN and BMP signaling. They found that exposure to BMP2 (112261) increased PTEN protein levels in the breast cancer cell line MCF-7. The increase in PTEN protein was rapid and was not due to an increase in new protein synthesis, suggesting that BMP2 stimulation inhibited PTEN protein degradation. BMP2 treatment of MCF-7 cells decreased the association of PTEN with 2 proteins in the degradative pathway, UBE2L3 (603721) and UBE2E3 (604151). Waite and Eng (2003) suggested that BMP2 exposure may regulate PTEN protein levels by decreasing PTEN's association with the degradative pathway, which may explain how BMPR1A may act as a minor susceptibility gene for PTEN-mutation-negative Cowden syndrome.
In studies of lymphoblastoid cell lines from patients with fibrodysplasia ossificans progressiva (FOP; 135100) and controls, de la Pena et al. (2005) found that FOP lymphocytes expressed 6-fold higher levels of BMPR1A on the cell surface compared with control cells and displayed a marked reduction in ligand-stimulated internalization and degradation of BMPR1A. In control cells, BMP4 (112262) treatment increased BMPR1A phosphorylation; in FOP cells, BMPR1A was phosphorylated at a high level in the absence of the ligand and showed no increase in response to BMP4. After treatment with the BMP antagonist noggin (602991), BMPR1A phosphorylation decreased in control cells but remained constant in FOP cells, indicating that BMPR1A hyperphosphorylation is independent of ligand stimulation in FOP cells. De la Pena et al. (2005) concluded that altered BMP receptor trafficking may play a significant role in FOP pathogenesis.
Using RT-PCR, immunofluorescence, and flow cytometric analyses, Cejalvo et al. (2007) demonstrated that human thymus and cortical epithelial cells produced BMP2 and BMP4 and that both thymocytes and thymic epithelium expressed the molecular machinery to respond to these proteins. The receptors BMPR1A and BMPR2 (600799) were mainly expressed by cortical thymocytes, whereas BMPR1B (603248) was expressed in the majority of thymocytes. BMP4 treatment of chimeric human-mouse fetal thymic organ cultures seeded with CD34 (142230)-positive human thymic progenitors resulted in reduced cell recovery and inhibition of differentiation of CD4 (186940)/CD8 (see 186910) double-negative to double-positive stages. Cejalvo et al. (2007) concluded that BMP2 and BMP4 have a role in human T-cell differentiation.
Ide et al. (1998) used fluorescence in situ hybridization and radiation hybrid mapping to localize the BMPR1A gene to human chromosome 10q22.3. By analysis of a monochromosome hybrid mapping panel and by FISH, Astrom et al. (1999) mapped the BMPR1A gene to chromosome 10q23. They identified a related intronless sequence on chromosome 6q23. Astrom et al. (1999) stated that the mouse Bmpr1a gene maps to a region of chromosome 14 that shows homology of synteny to human chromosome 10.
Delnatte et al. (2006) demonstrated de novo deletion of BMPR1A and the contiguous PTEN gene (601728) on chromosome 10q in 4 unrelated children with juvenile polyposis of infancy (see 612242). One of the children was a girl with extradigestive features suggesting Bannayan-Riley-Ruvalcaba syndrome (BRRS; 158350). She presented with macrocephaly at birth. Severity of gastrointestinal bleeding and diarrhea led to colectomy at age 10 months. The child died at age 3 years because of recurrent bleeding from polyps and inanition. Because of the features of BRRS, a search for a germline mutation of PTEN was performed. Although no mutation was found, a large deletion of the PTEN and BMPR1A loci was indicated by absence of paternal markers. Another of the 4 patients presented with more than 50 juvenile polyps within the entire colon and duodenum by age 18 months.
Juvenile polyposis (174900) is an autosomal dominant gastrointestinal hamartomatous polyposis syndrome in which patients are at risk for developing gastrointestinal cancers. The affected members in some families with juvenile polyposis showed germline mutations in the MADH4 gene (SMAD4; 600993), and mutations in the PTEN gene (601728) have been described in a few families. In an attempt to define the remaining genetic heterogeneity, Howe et al. (2001) used a genomewide screen in 4 juvenile polyposis kindreds without germline mutations in either MADH4 or PTEN and identified linkage with markers from chromosome 10q22-q23 (maximum lod score = 4.74 at theta = 0.00). They found no recombinants using markers developed from the vicinity of the BMPR1A gene. Genomic sequencing of BMPR1A in each of these juvenile polyposis kindreds disclosed germline nonsense mutations in all affected kindred members but not in normal individuals. These findings indicated involvement of an additional gene in the transforming growth factor-beta superfamily in the genesis of juvenile polyposis, and documented an unanticipated function for bone morphogenetic protein in colonic epithelial growth control.
Friedl et al. (2002) examined 29 patients with the clinical diagnosis of juvenile polyposis for germline mutations in the MADH4 or BMPR1A genes and identified MADH4 mutations in 7 (24%) and BMPR1A mutations in 5 patients (17%). A remarkable prevalence of massive gastric polyposis was observed in patients with MADH4 mutations when compared with patients with BMPR1A mutations or without identified mutations. This, they claimed, was the first genotype-phenotype correlation observed in juvenile polyposis.
Zhou et al. (2001) searched for germline mutations in BMPR1A in a series of familial and isolated European probands with juvenile polyposis syndrome and without germline mutations of MADH4. Ten of 25 (40%) probands were found to have germline BMPR1A mutations, 8 of which resulted in truncated receptors and 2 of which resulted in missense alterations: cys124 to arg (C124R; 601299.0006) and cys376 to tyr (C376Y; 601299.0007). Almost all available component tumors from mutation-positive cases showed loss of heterozygosity (LOH) in the BMPR1A region, whereas those from mutation-negative cases did not. Zhou et al. (2001) concluded that germline BMPR1A mutations cause a significant proportion of cases of juvenile polyposis.
Of 4 Korean patients with juvenile polyposis syndrome, Kim et al. (2003) identified 3 mutations in the MADH4 gene and 1 in the BMPR1A gene (601299.0008).
In 77 different familial and sporadic cases of juvenile polyposis, Howe et al. (2004) identified germline MADH4 mutations in 14 cases (18.2%) and BMPR1A mutations in 16 cases (20.8%). The authors noted that because mutations were not found in more than half of the patients with juvenile polyposis, either additional predisposing genes remain to be discovered or alternative means of inactivation of the 2 known genes account for these cases.
In affected members of a 3-generation Singapore Chinese family with hereditary mixed polyposis (HMPS2; 610069), Cao et al. (2006) identified heterozygosity for an 11-bp deletion in the BMPR1A gene (601299.0009).
Delnatte et al. (2006) described 4 unrelated children with juvenile polyposis of infancy (see 612242). They showed that these children were heterozygous for de novo germline deletion encompassing 2 contiguous genes, PTEN (601728) and BMPR1A. They hypothesized that juvenile polyposis of infancy is caused by the deletion of these 2 genes and that the severity of the disease reflects cooperation between these tumor suppressor genes.
Associations Pending Confirmation
D'Alessandro et al. (2016) performed whole-exome sequencing in 81 unrelated probands with atrioventricular septal defect (AVSD; see 606215) to identify potential causal variants in a comprehensive set of 112 genes with strong biological relevance to AVSD. A significant enrichment of rare and rare damaging variants was identified in the gene set, compared with controls (odds ratio (OR) 1.52; 95% confidence interval (CI), 1.35-1.71; p = 4.8 x 10(-11)). The enrichment was specific to AVSD probands, compared with a cohort without AVSD with tetralogy of Fallot (OR 2.25; 95% CI, 1.84-2.76; p = 2.2 x 10(-16)). Six genes, including BMPR1A, were enriched for rare variants in AVSD compared with controls. The findings were confirmed in a replication cohort of 81 AVSD probands. D'Alessandro et al. (2016) concluded that mutations in genes with strong biological relevance to AVSD, including syndrome-associated genes, can contribute to AVSD, even in those with isolated heart disease. Three rare nonsynonymous variants in BMPR1a were identified in 3.7% of AVSD cases, compared with 0.7% of controls from the Exome Variant Server (EVS) (OR 5.3; p = 0.02). All 3 missense variants were exceptionally rare and predicted to be damaging. Two probands had isolated cardiac disease, 1 also had learning and psychiatric disabilities and cervical spine anomalies, and 2 had left superior vena cava to coronary sinus.
Yoon et al. (2005) found that, although mice deficient in either Bmpr1a or Bmpr1b in cartilage form intact cartilaginous elements, double mutants develop severe generalized chondrodysplasia.
Liu et al. (2005) demonstrated that mice with conditional inactivation of the Bmpr1a gene in the facial primordia developed completely penetrant, bilateral cleft lip/palate (119530) with arrested tooth formation. The cleft secondary palate of Bmpr1a-mutant embryos was associated with diminished cell proliferation in maxillary process mesenchyme and defective anterior posterior patterning. In contrast, the mutant mice showed elevated apoptosis in the fusing lip region of the medial nasal process. Conditional inactivation of the Bmp4 gene resulted in delayed fusion of the medial nasal process to form the lip, resulting in isolated cleft lip in all mouse embryos at 12 days after conception. However, cleft lip was only present in 22% of mouse embryos at 14.5 days after conception, indicating spontaneous repair of cleft lip in utero (see 600625). The findings implicated a BMP4-BMPR1A genetic pathway that functions in lip fusion, and revealed that BMP signaling has distinct roles in lip and palate fusion.
Schulz et al. (2013) generated mice lacking the Bmpr1a gene in all cells descending from the Myf5 (159990)+ lineage, which are the cells that generate constitutive brown adipose tissue. No apparent changes in morphology, proliferation, or apoptosis were observed during early embryonic stages, but there was reduced constitutive brown fat formation starting at embryonic day 16.5. These mice were born runted and stayed smaller throughout life, and the reduction of constitutive brown adipose tissue mass remained highly significant in adult mice. This lack of constitutive brown adipose tissue resulted in increased sympathetic input to white adipose tissue, thereby promoting formation of recruitable brown adipose tissue within white fat deposits. This compensatory mechanism, aimed at restoring total brown fat-mediated thermogenic capacity in the body, is sufficient to maintain normal temperature homeostasis and resistance to diet-induced obesity. Schulz et al. (2013) concluded that their data suggested an important physiologic crosstalk between constitutive and recruitable brown fat cells.
In a kindred with juvenile polyposis (174900), Howe et al. (2001) found that affected members had a 4-bp deletion in exon 1 (44-47delTGTT) of the BMPR1A gene, resulting in a stop codon at nucleotides 104-106.
Howe et al. (2001) found that affected members of a family with juvenile polyposis syndrome (174900) had a C-to-T transition at nucleotide 715 of the BMPR1A gene, changing codon 239 from glutamine to a stop codon (Q239X).
In a kindred with juvenile polyposis (174900), Howe et al. (2001) found that affected members had a G-to-A transition at nucleotide 812, changing a tryptophan to a stop codon (trp271 to ter; W271X).
In a kindred with juvenile polyposis (174900), Howe et al. (2001) found that affected members had a 1-bp deletion in exon 8 of the BMPR1A gene (961delC), creating a stop at the next codon.
Zhou et al. (2001) identified a patient with a germline missense mutation, ala338 to asp (A338D), in exon 8 of BMPR1A. The proband had only colonic polyposis, which comprised hamartomatous and adenomatous polyps and began at the age of 16 years, and lipomas. Her family history, however, included individuals with breast cancer, renal-cell carcinoma, brain tumor(s), or melanoma. Taken together, these features constituted the minimum criteria (i.e., 1 major and 3 minor) for the diagnosis of Cowden syndrome (158350) (Eng, 2000). Zhou et al. (2001) suggested that BMPR1A mutation may define a small subset of cases of Cowden syndrome/Bannayan-Riley-Ruvalcaba syndrome (158350) with specific colonic phenotype.
In a patient with juvenile polyposis syndrome (174900), Zhou et al. (2001) identified a cys124-to-arg (C124R) mutation in the BMPR1A gene.
In a patient with juvenile polyposis syndrome (174900), Zhou et al. (2001) identified a cys376-to-tyr (C376Y) mutation in the BMPR1A gene.
In a Korean patient with juvenile polyposis syndrome (174900), Kim et al. (2003) identified a germline met470-to-thr (M470T) mutation in exon 10 of the BMPR1A gene.
In affected members of a 3-generation Singapore Chinese family with hereditary mixed polyposis (HMPS2; 610069), which they called 'family 2,' Cao et al. (2006) identified heterozygosity for an 11-bp deletion at codon 42 in exon 2 of the BMPR1A gene, predicted to cause a frameshift and a truncation deleting all the functional domains of BMPR1A. The mutation was not found in any unaffected family members.
Astrom, A.-K., Jin, D., Imamura, T., Roijer, E., Rosenzweig, B., Miyazono, K., ten Dijke, P., Stenman, G. Chromosomal localization of three human genes encoding bone morphogenetic protein receptors. Mammalian Genome 10: 299-302, 1999. [PubMed: 10051328] [Full Text: https://doi.org/10.1007/s003359900990]
Cao, X., Eu, K. W., Kumarasinghe, M. P., Li, H. H., Loi, C., Cheah, P. Y. Mapping of hereditary mixed polyposis syndrome (HMPS) to chromosome 10q23 by genomewide high-density single nucleotide polymorphism (SNP) scan and identification of BMPR1A loss of function. J. Med. Genet. 43: e13, 2006. Note: Electronic Article. [PubMed: 16525031] [Full Text: https://doi.org/10.1136/jmg.2005.034827]
Cejalvo, T., Sacedon, R., Hernandez-Lopez, C., Diez, B., Gutierrez-Frias, C., Valencia, J., Zapata, A. G., Varas, A., Vicente, A. Bone morphogenetic protein-2/4 signalling pathway components are expressed in the human thymus and inhibit early T-cell development. Immunology 121: 94-104, 2007. [PubMed: 17425602] [Full Text: https://doi.org/10.1111/j.1365-2567.2007.02541.x]
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de la Pena, L. S., Billings, P. C., Fiori, J. L., Ahn, J., Kaplan, F. S., Shore, E. M. Fibrodysplasia ossificans progressiva (FOP), a disorder of ectopic osteogenesis, misregulates cell surface expression and trafficking of BMPRIA. J. Bone Miner. Res. 20: 1168-1176, 2005. [PubMed: 15940369] [Full Text: https://doi.org/10.1359/JBMR.050305]
Delnatte, C., Sanlaville, D., Mougenot, J.-F., Vermeesch, J.-R., Houdayer, C., de Blois, M. C., Genevieve, D., Goulet, O., Fryns, J.-P., Jaubert, F., Vekemans, M., Lyonnet, S., Romana, S., Eng, C., Stoppa-Lyonnet, D. Contiguous gene deletion within chromosome arm 10q is associated with juvenile polyposis of infancy, reflecting cooperation between the BMPR1A and PTEN tumor-suppressor genes. Am. J. Hum. Genet. 78: 1066-1074, 2006. [PubMed: 16685657] [Full Text: https://doi.org/10.1086/504301]
Eng, C. Will the real Cowden syndrome please stand up: revised diagnostic criteria. J. Med. Genet. 37: 828-830, 2000. [PubMed: 11073535] [Full Text: https://doi.org/10.1136/jmg.37.11.828]
Eng, C. To be or not to BMP. Nature Genet. 28: 105-107, 2001. [PubMed: 11381248] [Full Text: https://doi.org/10.1038/88802]
Friedl, W., Uhlhaas, S., Schulmann, K., Stolte, M., Loff, S., Back, W., Mangold, E., Stern, M., Knaebel, H. P., Sutter, C., Weber, R. G., Pistorius, S., Burger, B., Propping, P. Juvenile polyposis: massive gastric polyposis is more common in MADH4 mutation carriers than in BMPR1A mutation carriers. Hum. Genet. 111: 108-111, 2002. [PubMed: 12136244] [Full Text: https://doi.org/10.1007/s00439-002-0748-9]
He, X. C., Zhang, J., Tong, W.-G., Tawfik, O., Ross, J., Scoville, D. H., Tian, Q., Zeng, X., He, X., Wiedemann, L. M., Mishina, Y., Li, L. BMP signaling inhibits intestinal stem cell self-renewal through suppression of Wnt-beta-catenin signaling. Nature Genet. 36: 1117-1121, 2004. [PubMed: 15378062] [Full Text: https://doi.org/10.1038/ng1430]
Howe, J. R., Bair, J. L., Sayed, M. G., Anderson, M. E., Mitros, F. A., Petersen, G. M., Velculescu, V. E., Traverso, G., Vogelstein, B. Germline mutations of the gene encoding bone morphogenetic protein receptor 1A in juvenile polyposis. Nature Genet. 28: 184-187, 2001. [PubMed: 11381269] [Full Text: https://doi.org/10.1038/88919]
Howe, J. R., Sayed, M. G., Ahmed, A. F., Ringold, J., Larsen-Haidle, J., Merg, A., Mitros, F. A., Vaccaro, C. A., Petersen, G. M., Giardiello, F. M., Tinley, S. T., Aaltonen, L. A., Lynch, H. T. The prevalence of MADH4 and BMPR1A mutations in juvenile polyposis and absence of BMPR2, BMPR1B, and ACVR1 mutations. J. Med. Genet. 41: 484-491, 2004. [PubMed: 15235019] [Full Text: https://doi.org/10.1136/jmg.2004.018598]
Ide, H., Saito-Ohara, F., Ohnami, S., Osada, Y., Ikeuchi, T., Yoshida, T., Terada, M. Assignment of the BMPR1A and BMPR1B genes to human chromosome 10q22.3 and 4q23-q24 by in situ hybridization and radiation hybrid mapping. Cytogenet. Cell Genet. 81: 285-286, 1998. [PubMed: 9730621] [Full Text: https://doi.org/10.1159/000015048]
Jamin, S. P., Arango, N. A., Mishina, Y., Hanks, M. C., Behringer, R. R. Requirement of Bmpr1a for mullerian duct regression during male sexual development. Nature Genet. 32: 408-410, 2002. [PubMed: 12368913] [Full Text: https://doi.org/10.1038/ng1003]
Kim, I.-J., Park, J.-H., Kang, H. C., Kim, K.-H., Kim, J.-H., Ku, J.-L., Kang, S.-B., Park, S. Y., Lee, J.-S., Park, J.-G. Identification of a novel BMPR1A germline mutation in a Korean juvenile polyposis patient without SMAD4 mutation. Clin. Genet. 63: 126-130, 2003. [PubMed: 12630959] [Full Text: https://doi.org/10.1034/j.1399-0004.2003.00008.x]
Liu, W., Sun, X., Braut, A., Mishina, Y., Behringer, R. R., Mina, M., Martin, J. F. Distinct functions for Bmp signaling in lip and palate fusion in mice. Development 132: 1453-1461, 2005. [PubMed: 15716346] [Full Text: https://doi.org/10.1242/dev.01676]
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ten Dijke, P., Ichijo, H., Franzen, P., Schulz, P., Saras, J., Toyoshima, H., Heldin, C.-H., Miyazono, K. Activin receptor-like kinases: a novel subclass of cell-surface receptors with predicted serine/threonine kinase activity. Oncogene 8: 2879-2887, 1993. [PubMed: 8397373]
Waite, K. A., Eng, C. BMP2 exposure results in decreased PTEN protein degradation and increased PTEN levels. Hum. Molec. Genet. 12: 679-684, 2003. [PubMed: 12620973]
Yoon, B. S., Ovchinnikov, D. A., Yoshii, I., Mishina, Y., Behringer, R. R., Lyons, K. M. Bmpr1a and Bmpr1b have overlapping functions and are essential for chondrogenesis in vivo. Proc. Nat. Acad. Sci. 102: 5062-5067, 2005. [PubMed: 15781876] [Full Text: https://doi.org/10.1073/pnas.0500031102]
Zhou, X. P., Woodford-Richens, K., Lehtonen, R., Kurose, K., Aldred, M., Hampel, H., Launonen, V., Virta, S., Pilarski, R., Salovaara, R., Bodmer, W. F., Conrad, B. A., and 17 others. Germline mutations in BMPR1A/ALK3 cause a subset of cases of juvenile polyposis syndrome and of Cowden and Bannayan-Riley-Ruvalcaba syndromes. Am. J. Hum. Genet. 69: 704-711, 2001. [PubMed: 11536076] [Full Text: https://doi.org/10.1086/323703]