Oculodentodigital Syndrome with Syndactyly Type III in a Pakistani consanguineous family

Abstract

Oculodentodigital syndrome (ODD; OMIM #164200) is a rare autosomal dominant disorder with pleiotropic effects. It is caused by mutation in gap junction protein α 1 (GJA1) gene which encodes connexion 43. ODD is characterised by symptoms i.e. craniofacial, neurologic, limb, ocular abnormalities, syndactyly type III of the hands, phalangeal abnormalities, diffuse skeletal dysplasia, enamel dysplasia, and hypotrichosis. To study the Molecular Genetics of Oculodentodigital syndrome. Our current study includes a Pakistani family affected with ODD. Clinical evaluation revealed that this family shows typical form of ODD with Syndactyly type III. Mutations in GJA1 have been reported in ODD and also in syndactyly type III. In this study we sequenced the coding exons of GJA1 gene in affected and normal individuals of the family for mutation detection. Direct sequencing of the affected individuals showed a mutation at the nucleotide position 389 T>C. This mutation changed the codon 130 from Isoleucine to Threonine. Normal family members did not show this mutation. Our study showed no gross neurological upset with I130T mutation in GJA1 gene. This may present novel phenotypic outcome with the I130T. The study will help in better understanding of pathophysiology of oculodentodigital syndrome and type III syndactyly.