DIABETES EPIDEMIOLOGY Vitamin D receptor polymorphism and susceptibility to type 1 diabetes in chilean subjects: A case-parent study

Several reports have found a relation between polymorphisms of the vitamin D receptor gene (VDR) and the development of type 1 diabetes. We have examined the association of three VDR polymorphism with type 1 diabetes in 59 Chilean case-parents trios. Genotyping for Bsm1, Apa1 and Taq1 polymorphism were performed. Transmission/ disequiibrium tests were used to assess gene-disease associations through the evaluation of allelic transmission to affected offspring. Non-significant increased transmissions of B allele (probability of transmission 1⁄4 52.5%, p 1⁄4 0.69), A allele (probability of transmission 1⁄4 58.4%, p 1⁄4 0.17) and T allele (probability of transmission 1⁄4 52.0%, p 1⁄4 0.77) were estimated in Bsm1, Apa1 and Taq1 sites, respectively. Haplotype-based analyses showed non-significant preferential transmissions (global p 1⁄4 0.52). The present study does not support the hypothesis of a significant contribution of VDR alleles in the etiology of type 1 diabetes of Chilean cases.