Int J Infect Dis 2020 Mar 13;92:21-28. Epub 2019 Dec 13.
Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil; Faculdade de Medicina, Universidade Federal da Bahia, Salvador, Bahia, Brazil; Multinational Organization Network Sponsoring Translational and Epidemiological Research (MONSTER) Initiative, Fundação José Silveira, Salvador, Bahia, Brazil; Division of Infectious Diseases, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA; Wellcome Centre for Infectious Disease Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa; Universidade Salvador (UNIFACS), Laureate Universities, Salvador, Bahia, Brazil; Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil. Electronic address:
Background: Host genetic polymorphisms may be important in determining susceptibility to Mycobacterium tuberculosis (Mtb) infection, but their role is not fully understood. Detection of microbial DNA and activation of type I interferon (IFN) pathways regulate macrophage responses to Mtb infection.
Methods: We examined whether seven candidate gene SNPs were associated with tuberculin skin test (TST) positivity in close contacts of microbiologically confirmed pulmonary TB patients in Brazil. Independent associations with TST positivity were tested using multivariable logistic regression (using genotypes and clinical variables) and genetic models.
Results: Among 482 contacts of 145 TB index cases, 296 contacts were TST positive. Multivariable regression analysis adjusted for population admixture, age, family relatedness, sex and clinical variables related to increased TB risk demonstrated that SNPs in PYHIN1-IFI16-AIM2 rs1101998 (adjusted OR [aOR]: 3.72; 95%CI=1.15-12.0; p=0.028) and in PYHIN1-IFI16-AIM2 rs1633256 (aOR=24.84; 95%CI=2.26-272.95; p=0.009) were associated with TST positivity in a recessive model. Furthermore, an IRF7 polymorphism (rs11246213) was associated with reduced odds of TST positivity in a dominant model (aOR: 0.50, 95%CI: 0.26-0.93; p=0.029).
Conclusions: Polymorphisms in PYHIN1-IFI16-AIM2 rs1633256, rs1101998 and in IRF7 rs11246213 were associated with altered susceptibility to Mtb infection in this Brazilian cohort.