Genetic Polymorphisms ofIL1B, IL6,andTNFαin a Chinese Han Population with Pulmonary Tuberculosis

Abstract

Background. The factors that predispose to pulmonary tuberculosis (PTB) are not fully understood. Previous studies have shown that cytokine gene polymorphisms were associated with PTB.Objectives. In this study, we have investigated the relationship betweenILB,IL6,andTNFαpolymorphisms and a predisposition toMycobacterium tuberculosis(MTB) infection and PTB.Methods. A total of 209 cases of PTB, 201 subjects with latent TB infection (LTBI), and 204 healthy controls (HCS) were included in this study. Logistic regression analyses under allelic, homozygous, and heterozygous models were used to calculatePvalues, odds ratios (ORs), and 95% confidence intervals (CIs) for assessing the association between single nucleotide polymorphisms (SNPs) and disease risk, adjusting for sex and age. Genotyping was conducted using the improved multiplex ligase detection reaction (iMLDR) method.Results. When comparing PTB patients with LTBI subjects, significant associations with disease development were observed for SNPs ofIL6andTNFα. When comparing LTBI subjects with HCS,IL1Bpolymorphisms were significantly associated with LIBI. Haplotype analyses suggested that the CGG haplotype ofIL1Bwas associated with an increased risk of PTB (P=0.039, OR = 1.34, 95% CI: 1.01–1.76), while the TTGCG haplotype ofTNFαwas a protective factor against PTB (P=0.039, OR = 0.66, 95% CI: 0.44–0.98).Conclusion. Our study demonstrated thatIL1Bvariants were related to LTBI andIL6andTNFαvariants were associated with PTB.