A Deleterious Founder Mutation in the BMPER Gene Causes Diaphanospondylodysostosis (DSD)

作者:Ben Neriah Ziva; Michaelson Cohen Rachel*; Inbar Feigenberg Michal; Nadjari Michael; Zeligson Sharon; Shaag Avraham; Zenvirt Shamir; Elpeleg Orly; Levy Lahad Ephrat
来源:American Journal of Medical Genetics, Part A, 2011, 155A(11): 2801-2806.
DOI:10.1002/ajmg.a.34240

摘要

Diaphonospondylodysostosis (DSD) is a rare, recessively inherited, lethal skeletal dysplasia, characterized by severe spinal ossification, segmentation defects, and renal cystic dysplasia with nephrogenic rests. We hereby present three affected individuals: two children and a fetus from two unrelated East Jerusalem Arab-Muslim families. Whereas most fetuses die in utero or perinatally, one of the children survived to 15 months. Homozygosity mapping in the two families demonstrated a single common 3.87Mb region on chromosome 7, ruling out previously known spondylocostal/spondylothoracic dysostosis loci. The 15 protein coding genes in the region were prioritized, and some were sequenced. A single, novel deleterious mutation, Q104X, was detected in the bone morphogenetic protein-binding endothelial regulator protein (BMPER) gene, recently reported to be mutated in other DSD patients [Funari et al., 2010]. The novel mutation we identified is an ancestral founder allele, as evidenced by a shared 440 SNP haplotype, and its frequency in the general Arab population is estimated to be <1:123. Our findings confirm loss of BMPER function as a cause of axial versus appendicular skeletal defects, and suggest that less deleterious mutations may be involved in milder axial skeleton abnormalities.