Association between IL-1 gene polymorphisms and tuberculosis susceptibility in the Chinese Tibetan population

Interleukin-1 (IL-1) gene is known to be implicated in tuberculosis (TB). The present case-control study was designed to investigate whether IL-1 polymorphisms associated with TB susceptibility in a Chinese Tibetan cohort. 300 Tibetan tuberculosis patients and 300 healthy controls were recruited for 12 single-nucleotide polymorphisms (SNPs) genotyping of IL-1 gene via Sequenom MassARRAY analysis. The odds ratio (OR) and 95% confidence interval (CI) were analyzed by unconditional logistic regression to evaluate the effect of polymorphisms on the risk of tuberculosis. Among genotyped SNPs, a significant high risk between TB and SNP rs3783550 G/T, rs3783546 G/C, rs2856838 A/G, rs1609682 G/T, rs3783521 A/G genotype within IL-1α as well as rs1143623 G/G genotype within IL-1β was found based on multiple model analysis. In addition, IL-1α SNPs mapped in a 10 kb LD block with D'>0.98, suggesting that a significant linkage disequilibrium presence among these SNPs, and "TCATG" haplotype of IL-1α SNPs with a 1.47-fold risk for TB was observed (P = 0.007). In conclusion, our data shed new light on how IL-1 SNPs may contribute to tuberculosis susceptibility in the Chinese Tibetan population.