A Functional Polymorphism in Promoter of the CXCL10 Gene (-135 G/A) Associated With Pulmonary Tuberculosis

Background: Genetic variation influences susceptibility/resistance to tuberculosis. CXCL10 is involved in T-cell migration and stimulation of natural killer cells in Mycobacterium tuberculosis infection. Objectives: We aimed to investigate the genetic polymorphisms in promoter of the CXCL10 gene in patients with pulmonary tuberculosis (PTB) and healthy controls, to clarify whether polymorphisms in the CXCL10 gene is associated with tuberculosis. Patients and Methods: This study was performed on 150 patients with PTB as well as 150 healthy subjects. Polymorphism of CXCL10 (-135 G/A) was determined using amplification refractory mutational system-polymerase chain reaction (ARMS-PCR). Results: There were significant differences in genotype and allele frequencies of the CXCL10 gene -135 G/A polymorphism between the groups. GA and AA genotypes were protective against tuberculosis in comparison with GG genotype (OR = 0.19, 95% CI = 0.10-0.36, P < 0.001; and OR = 0.12, 95% CI = 0.04-0.43, P < 0.001, respectively). Furthermore, A allele decreased the risk of PTB in comparison with G allele (OR = 0.55, 95% CI = 0.39-0.77, P < 0.001). Conclusions: Significant association was found between the CXCL10 -135 G/A promoter variant and host resistance to PTB in a sample of Iranian population