A single nucleotide polymorphism in the interferon-γ gene (<i>IFNG</i> +874 T/A) is associated with susceptibility to tuberculosis

Abstract

// Zhang Wei 1,* , Shen Wenhao 2,* , Mi Yuanyuan 3 , Li Yang 1 , Zhou Daming 1 , Xian Jiangchun 1 and Jiang Jijun 1 1 Department of Infectious Disease, Taizhou People&rsquo;s Hospital, Taizhou, China 2 Department of Oncology, Taizhou People&rsquo;s Hospital, Taizhou, China 3 Department of Urology, Third Affiliated Hospital of Nantong University, Wuxi, China * These authors have contributed equally to this work Correspondence to: Zhang Wei, email: // Keywords : Interferon-&gamma;; pulmonary tuberculosis; extra-pulmonary tuberculosis; polymorphism; meta-analysis; Immunology and Microbiology Section; Immune response; Immunity Received : January 07, 2017 Accepted : March 30, 2017 Published : April 20, 2017 Abstract Interferon-&gamma; (Interferon gamma, IFNG) is an important cytokine involved in providing resistance to mycobacterial diseases. Common variants of IFNG , such as IFNG +874 T/A(rs2430561), may be related to tuberculosis susceptibility, but this association has not been consistently observed. We performed an updated meta-analysis to evaluate the association between the IFNG +874 T/A (rs2430561) polymorphism and tuberculosis susceptibility. PubMed and SinoMed databases were searched up to October 2016, and odds ratios (OR) and 95% confidence intervals (CI) were used to assess the association strength. Based on search criteria for manuscripts reporting tuberculosis susceptibility and its relationship with the IFNG +874 T/A(rs2430561)polymorphism, 42 case-control studies from 39 different articles were retrieved. Significantly positive, decreased, and protective associations were found between the IFNG +874 T/A(rs2430561)polymorphism and tuberculosis risk in five genetic models. Moreover, in the stratified subgroup analysis, a protective relationship was detected in four different ethnicities and sources of the control groups. Furthermore, the IFNG +874 T/A(rs2430561)polymorphism played an important role in protecting individuals from both pulmonary tuberculosis and extra-pulmonary tuberculosis. Our meta-analysis suggests that the IFNG +874 T/A(rs2430561)polymorphism is potentially associated with tuberculosis susceptibility and may be used as a predictive biomarker. Further studies with larger sample sizes and consideration of gene-environment interactions should be conducted to elucidate the role of IFNG +874 T/A(rs2430561) polymorphism in tuberculosis susceptibility.