VDR is found on the surface of almost all human cells, a distribution that enables the multidirectional impact of vitamin D. Studies on associations between VDR gene polymorphisms, namely Fok-I, Bsm-I, Apa-I and Taq-I, and T1DM susceptibility are inconsistent and inconclusive. The gene discussed is VDR; the disease is type 1 diabetes mellitus.