IL23R(Arg381Gln) functional polymorphism is associated with active pulmonary tuberculosis severity

Abstract

The purpose of our study was to investigate the association between a functional single nucleotide polymorphism (SNP) in the interleukin-23 receptor gene (IL23R; rs11209026, 1142 Gwild type → A reduced function, Arg381Gln) and disease severity outcome in pulmonary tuberculosis (TB) in the Tunisian population. SNP was investigated in a population of 168 patients with active pulmonary TB (cases were stratified into patients with minimal/moderate lung involvement, i.e., patients with minimal/moderate disease [Pmd], and patients with extensive lung involvement, i.e., patients with active disease [Pad]) and 150 healthy subjects. Genotype analyses were carried out using the PCR-restriction fragment length polymorphism method. We have found that the IL23R reduced-function allele 1142A and genotypes AA and AG were overrepresented, especially in the Pad subgroup compared with the control group (51% versus 18% [P = 10-8], 33% versus 5% [P = 10-8], and 36% versus 26% [P = 5 × 10 -3], respectively). Additionally, comparison of the Pad and the Pmd groups showed that the A allele and AA genotype seemed to be associated with 2.79-fold (P = 4 × 10-5) and 7.74-fold (P = 10-5) increased risks of TB with minimal/moderate lung involvement, respectively. Our results demonstrate that the reduced-function polymorphism 1142G → A encoded by IL23R influences the outcome of disease severity of active pulmonary TB in Tunisian patients. Copyright © 2012, American Society for Microbiology. All Rights Reserved.