Homozygous stop mutation in the SNX10 gene in a consanguineous Iraqi boy with osteopetrosis and corpus callosum hypoplasia

Abstract

Recently a mutation in the SNX10 gene that belongs to the sorting nexin family was identified as a cause of a new subset of human autosomal recessive osteopetrosis. Here, we identified a novel homozygous mutation (c.46C > T, p.Arg16X) in SNX10, in an Iraqi boy from a consanguineous family with a history of infantile osteopetrosis. The proband exhibited macrocephaly, prominent forehead, proptosis of the eyes, strabismus, splenomegaly and joint hyperlaxity. Bone X-rays showed increased bone density, metaphyseal under-modelling, transverse alternating bands of greater and lesser density in tubular bones, anteriorly notched vertebral bodies and bone-in-bone appearance. Brain atrophy, external hydrocephalus and thin corpus callosum were noted at the brain MRI and CT scan. Blood test results revealed the presence of anaemia and leukopenia. Our findings confirm the role of SNX10 in autosomal recessive osteopetrosis and help to better define the core set of manifestations associated with this new pathological entity.