A systematic review of natural resistance-associated macrophage protein 1 (NRAMP1) gene and susceptibility to tuberculosis: What is the link for ocular tuberculosis?

Abstract

Link of Video Abstract: https://youtu.be/hxFKCtWwc3c   Introduction: The host genetic factors play a crucial role in determining susceptibility to tuberculosis (TB), and one such candidate gene is Natural Resistance-Associated Macrophage Protein 1 (NRAMP1). NRAMP1 is involved in the regulation of intracellular iron homeostasis, an essential nutrient for MTb survival within macrophages. Several polymorphisms of the NRAMP1 gene have been extensively studied for their association with TB susceptibility. However, the specific role of these NRAMP1 gene polymorphisms in the development of ocular tuberculosis, a rare but potentially severe form of TB, remains poorly understood. Methods: This study was a systematic review conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). A comprehensive search was performed in the PubMed, Cochrane, and Science Direct databases for original, full-text studies of NRAMP1 gene related to tuberculosis infection. Ethnic, polymorphisms of NRAMP1 evaluated, and its association to TB susceptibility were recorded and summarized qualitatively. Results: There were 41 studies included in our systematic review. No study of NRAMP1 gene polymorphism in regards to ocular tuberculosis was found. Polymorphisms of the NRAMP1 gene, such as 3'UTR TGTG ins/del, D543N, INT4, and (GT)n, have been investigated for their potential role in determining the susceptibility or immunity to Mycobacterium tuberculosis infection. However, the findings regarding the relationship between NRAMP1 gene polymorphism and tuberculosis are still inconsistent, with controversies and discrepancies among different studies. Conclusion: NRAMP1 gene polymorphisms showed important involvement to tuberculosis infection susceptibility, therefore its relation to ocular tuberculosis is suggested.