In this meta-analysis, a significant relationship was observed between TAP1 I333V gene polymorphism and T1DM in the allelic (OR: 1.35), dominant (OR: 1.462), homozygous (OR: 1.725), heterozygous (OR: 1.430) and additive (OR: 1.348) genetic models, especially among Caucasians. The gene discussed is TAP1; the disease is type 1 diabetes mellitus.