Association of the polymorphism for toll-like receptor 2 with type 1 diabetes susceptibility

Type I diabetes mellitus (TIDM) is a T cell-mediated autoimmune disease in which pancreatic P cells are selectively destroyed. Although autoimmune diseases are driven by inappropriate adaptive immunity, innate immunity may play a role in the development of TIDM. We investigated the association of the genes for toll-like receptor 2 (TLR2), one of the key surface receptors on innate effectors, with TIDM in Korean patients. Genetic association analyses revealed that the genotype composed of the rare allele (CC) of TLR2 1350 showed weak and protective association with TIDM (OR = 1.7, 95% CI: 1.1-2.7; P < .05) irrespective of the duration of disease, age, and antoantibody status. One of the TLR2 SNP haplotypes, TLR2-Ht4, was strongly associated with TIDM in that those subjects having more than one copy of Ht4 showed stron protection from developing T1DM (OR =: 90.5; 95% CI: 13.8-235.7; P < 10(-5)). The TLR2 polymorphisms are associated with TIDM, and distribution differences between TIDM versus controls were not influenced by the HLA genes. There is a close relationship between innate and adaptive immunity.