Exploring IFN-γ +874T/A gene polymorphisms among suspected tuberculosis cases in Ouagadougou, Burkina Faso

Interferon-gamma (IFN-γ) plays a crucial role in resistance to mycobacterial infections, as it is a regulatory cytokine that acts as a pro-inflammatory mediator. Consequently, variants in the gene encoding this cytokine may be associated with a high risk of contracting pulmonary tuberculosis. The present study aimed to investigate the genetic susceptibility of polymorphisms in the gene coding for IFN-γ to infection by Mycobacterium tuberculosis in Burkina Faso. This cross-sectional study was conducted from May 2023 to January 2024. Venous blood was collected from suspected cases. Tuberculosis was confirmed by GeneXpert (CEPHEID). Human genomic DNA was extracted using the salting-out extraction technique, followed by the amplification and genotyping of IFN-γ gene polymorphisms,through the conventional PCR. Statistical analyses were performed using the SPSS and Epi info software. A total of 168 participants were included in the study, with an average age of 38.58 ±14.88, the majority of whom were men (76.19%). In our study population, 73.2% (123/168) were confirmed positive for tuberculosis. Some 46.4% (78/168) of the previous cases were contacts. Of these contact cases, 82.05% (64/78) were GeneXpert positive. The genotypic frequencies of the IFN-γ gene were distributed as follows: 73.3% (AA), 21.8% (AT) and 4.9% (TT), with a frequency of 84.2% for the A allele versus 15.8% for the mutated T allele. No statistically significant association was found between IFN-γ gene polymorphisms and M. tuberculosis infection in Burkina Faso. IFN-γ gene polymorphisms (IFN +874T/A) do not appear to be associated with M. tuberculosis infection in Burkina Faso.