Mutations in NOTCH2 in families with Hajdu-Cheney syndrome.

Department of Human Genetics, McGill University and Genome Quebec Innovation Centre, Canada.
Human Mutation (Impact Factor: 5.21). 06/2011; 32(10):1114-7. DOI: 10.1002/humu.21546
Source: PubMed

ABSTRACT Hajdu-Cheney syndrome (HCS) is a rare genetic disorder whose hallmark is acro-osteolysis, shortening of terminal phalanges, and generalized osteoporosis. We assembled a cohort of seven families with the condition and performed whole exome resequencing on a selected set of affected patients. One protein-coding gene, NOTCH2, carried heterozygous truncating variants in all patients and their affected family members. Our results replicate recently published studies of HCS and further support this as the causal gene for the disorder. In total, we identified five novel and one previously reported mutation, all clustered near the carboxyl terminus of the gene, suggesting an allele specific genotype-phenotype effect since other mutations in NOTCH2 have been reported to cause a form of Alagille syndrome. Notch-mediated signaling is known to play a role in bone metabolism. Our results support a potential therapeutic role for Notch pathways in treatment of osteoporosis.

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    ABSTRACT: Hajdu-Cheney syndrome (HCS) is a rare genetic disorder characterised by acro-osteolysis, skull deformation and generalised osteoporosis. Recently, truncating mutations in the last exon of NOTCH2, a protein-coding gene, were found to be responsible. We present the case of a young woman with HCS in whom clinical and radiologic diagnosis was confirmed with DNA tests.
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