Variants of HLA-DR2/DR51 group haplotypes and susceptibility to tuberculoid leprosy and pulmonary tuberculosis in Asian Indians.

This study reports our observations on the correlation between HLA-DR2 subtypes and their DR-DQ haplotypes in patients with tuberculoid (TT) leprosy and pulmonary tuberculosis (PTB). DRB11501 was significantly increased in patients with PTB (90%) as compared to controls (p < 0.05); whereas the prevalence of DRB11502 was significantly increased in patients with TT leprosy (p < 0.05), suggesting allele-specific binding of the pathogen to form disease-causing motifs to the T-cell receptor. Among DR2-DQ haplotypes, the deviation was noted in the distribution of unique and common haplotypes in patients with TT leprosy and PTB. A significant decrease of haplotype DRB11501-DRB50101-DQA10102-DQB10502 in TT leprosy and a significant increase of DRB11501-DRB50101-DQA10103-DQB10601 in PTB patients were observed. The occurrence of specific DR2 subtypes and their haplotypes in the two disease groups suggests their involvement in disease pathogenesis.