The variations of IL-23R are associated with susceptibility and severe clinical forms of pulmonary tuberculosis in Chinese Uygurs

BACKGROUND The incidence of tuberculosis (TB) remains high among Chinese Uygurs (a long-dwelling ethnic minority in Xinjiang) in China and the variants in IL-23R likely contribute to individual's diversity in host response during infection. METHODS A hospital based one to one matched case-control study was performed to assess the role of single nucleotide polymorphisms (SNPs) and copy number variation (CNV) of IL-23R in susceptibility and clinical features of pulmonary TB in Chinese Uygurs. Thirteen SNPs in IL-23R were genotyped by multiplex SNaPshot and a CNV was analyzed using Taqman real-time PCR in 250 pairs of pulmonary TB patients and controls. RESULTS The SNP rs7518660 (OR = 4.78, 95% CI 3.14-8.52) and the CNV in IL23R (OR = 2.75, 95% CI 1.51-4.98) were significantly associated with susceptibility to pulmonary TB. The SNP rs11465802 (OR = 3.23, 95% CI 1.85-5.62) was significantly associated with drug-resistance and the SNP rs1884444 (OR = 3.61, 95% CI 1.90-6.85) was significantly related to cavitary lesion in Chinese Uygurs. CONCLUSIONS Our study shows for the first time that SNP and CNV in IL23R were associated with susceptibility, drug resistance and cavity formation of pulmonary TB. Our findings indicate that these IL-23R polymorphisms may be considered as risk factors for active pulmonary TB and its severe clinical forms.