On the other hand, DRB1*0701, DQB1*0201 and DQA1*0201 were decreased in the multibacillary leprosy patients (MLP) compared to TT patients and controls, and DQB1*0503 was selectively decreased in TT patients, suggesting that these HLA alleles might play a role in modulating the immune response that determines the form of leprosy that develops in each patient.
With the purpose of identifying genes of susceptibility, the present study investigated the possible role of HLA-DRB1 and DQA1/DQB1 alleles in susceptibility to leprosy, and whether they account for the heterogeneity in immune responses observed following infection in a Southern Brazilian population.
We have conducted an association analysis of more than 1,500 individuals from different case-control and family studies, and observed consistent associations between genetic variants in both TLR1 and the HLA-DRB1/DQA1 regions with susceptibility to leprosy (TLR1 I602S, case-control P = 5.7 x 10(-8), OR = 0.31, 95% CI = 0.20-0.48, and HLA-DQA1rs1071630, case-control P = 4.9 x 10(-14), OR = 0.43, 95% CI = 0.35-0.54).