IL1R1 and IL1R2 polymorphisms were associated with tuberculosis risk: A pilot study.

BACKGROUND: Interleukin (IL)-1 has been reported to be involved in the development of tuberculosis (TB). IL1R1 and IL1R2 encode a cytokine receptor that belongs to the IL-1 receptor family. However, few studies have reported on the polymorphisms of IL1R1 and IL1R2 in TB patients.

METHODS: We investigated nine single-nucleotide polymorphisms (SNPs) in IL1R1 and IL1R2 in 300 TB patients and 300 controls, aiming to evaluate their association with TB risk. Odds ratios and 95% confidence intervals were calculated using unconditional logistic regression after adjusting for age and gender.

RESULTS: On comparing the allele frequencies of candidate SNPs, we found that the minor allele 'A' of rs4851527 in IL1R2 was associated with a decreased risk of TB, whereas the minor alleles of rs10490571, rs956730 and rs3917225 in IL1R1 were associated with an increased risk of TB (p < 0.05). In the genetic model analysis, we found that the allele 'A' of rs4851527 was correlated with a decreased risk of TB in a log-additive model, whereas the minor alleles of rs719250, rs3218977, rs10490571, rs956730 and rs3917225 were correlated with an increased risk of TB in dominant and log-additive models (p < 0.05). Additionally, we found three haplotypes that were associated with an increased risk of TB: TGCT and TGTT haplotypes constructed by rs11674595, rs4851527, rs719250 and rs3218896, as well as GA haplotype constructed by rs3218977 and rs2072472 (p < 0.05).

CONCLUSIONS: Our data shed new light on the association between genetic polymorphisms of IL1R1 and IL1R2 and TB susceptibility in the Chinese Han population.