Genetic polymorphisms of toll-like receptors in leprosy patients from southern Brazil.

Leprosy is a chronic disease and also a global health issue, with a high number of new cases per year. Toll-like receptors can respond to mycobacterial molecules in the early stage of infection. As important components of the innate immune response, alterations in genes coding for these receptors may contribute to susceptibility/protection against diseases. In this context, we used a case-control study model (183 leprosy cases vs. 185 controls) to investigate whether leprosy patients and the control group, in southern Brazil, have different frequencies in ( G>T; rs5743618), ( T>C, rs1816702 and rs4696483), and ( A>G, rs1927911) polymorphisms. Analysis of the 1805G>T polymorphism presented the genotype more frequently in the control group. T>C rs1816702 and T>C rs4696483, the T/T and C/T genotype, respectively, were more frequent in the control group than in leprosy patients, suggesting protection from leprosy when the T allele is present (rs4696483). Haplotype analyses between (rs5743618) and (rs1816702 and rs4696483) polymorphisms suggest risk for the presence of the TCC haplotype and protection in the presence of the TCT haplotype. This study suggests that polymorphisms in and are factors that may contribute to development/resistance of leprosy.