IL-10R1 S138G loss-of-function polymorphism is associated with extrapulmonary tuberculosis risk development in Tunisia.

There is considerable evidence that host genetic factors are important in determining susceptibility to mycobacterial infections. More recently, functional genetic mutations affecting IL-10 receptor 1 (IL-10R1) were described. In this study, we investigated the relationship of IL-10R1 S138G loss-of-function polymorphism (A536G: rs3135932) with susceptibility to active tuberculosis (TB) in Tunisian patients. A total of 168 patients with pulmonary TB, 55 with extrapulmonary TB, and 150 control subjects were studied. Genomic DNA samples were extracted from leukocytes and used to investigate S138G polymorphism in IL-10R1 gene by multiplex allele-specific polymerase chain reaction. Associations between G allele [odds ratio OR=5.01; 95% confidence intervals CI=2.58-9.77; P=10(-7)], GG genotypes [OR=9.06; 95% CI (1.58-67.33); correcting P-values using the Bonferroni method for multiple tests Pc=0.015] and AG genotype [OR=3.75; 95% CI (1.62-8.7); Pc=0.0012] with the risk development of active extrapulmonary TB were found. In contrast, the AA genotype was found to be associated with resistance to extrapulmonary TB [OR=0.19; 95% CI (0.09-0.42); Pc=6.10(-6)]. No association was found between S138G SNP and pulmonary TB. In conclusion, our study suggested the possible role of IL-10R1 S138G loss-of-function polymorphism in extrapulmonary TB susceptibility-resistance in Tunisia.