Genetic susceptibility in tuberculosis

Abstract

The importance of host genetic factors in determining susceptibility to tuberculosis (TB) has been studied extensively using various methods, such as case-control, candidate gene and genome-wide linkage studies. Several important candidate genes like human leucocyte antigen/alleles and non-human leucocyte antigen genes, such as cytokines and their receptors, chemokines and their receptors, pattern recognition receptors (including toll-like receptors, mannose binding lectin and the dendritic cell-specific intercellular adhesion molecule-3 grabbing nonintegrin), solute carrier family 11A member 1 (formerly known as natural resistance-associated macrophage protein 1) and purinergic P2X7 receptor gene polymorphisms, have been associated with differential susceptibility to TB in various ethnic populations. This heterogeneity has been explained by host-pathogen and gene-environment interactions and evolutionary selection pressures. Although the achievements of genetics studies might not yet have advanced the prevention and treatment of TB, researchers have begun to widen their scope of investigation to encompass these practical considerations.

Mal de Pott en un indígena colombiano

“…Además de los factores ya discutidos, se sabe de la existencia de polimorfismos genéticos que confieren propensión a la infección y el desarrollo de la enfermedad tuberculosa, y de otras infecciosas y no infecciosas, los cuales se han detectado en la población indígena y la negra (10,34,35).…”

“…Factores como la pobreza, el aislamiento geográfico, el abandono político, social y cultural, la discriminación, la desnutrición y el hacinamiento, hacen de estas minorías un grupo con gran riesgo de infectarse y enfermar de tuberculosis (9); además, los estudios genéticos han puesto en evidencia la existencia de polimorfismos genéticos que los hacen incluso más propensos a la infección (10).…”

Determination of the Cytokine Gene Polymorphism and Genetic Susceptibility in Tuberculosis Patients

“…Enfeksiyon hastalıklarında konak genetik faktörlerin rolünün ortaya çıkarılması, enfeksiyonlara yatkınlıkta bireysel direnç ya da duyarlılığın nedenlerini açıklayabilmektedir 15,16 . TB'ye karşı immün yanıt, antijen sunan hücreler ile lenfositler arasındaki etkileşim ve bu hücre tiplerinden salgılanan sitokinlerle düzenlenmektedir.…”

Infectious disease — a genetic view

“…The most consistent results were obtained with some HLA class II genes, and NRAMP1 (natural resistance associated macrophage protein I) / SLC11A1 (solute carrier family 11 member 1) [12,45]. Other genes shown to be involved in this process were the vitamin D receptor [46], SP110, the human homologue of the mouse gene Iprl (intracellular pathogen resistance 1) [47], genes for cytokines and their receptors [48], chemokines and their receptors, pattern recognition receptors (including toll-like receptors, mannose binding lectin and the dendritic cell-specific intercellular adhesion molecule-3 grabbing nonintegrin), and purinergic P2X7 receptor gene polymorphisms [49]. The overall effect described for these genes on susceptibility to disease is weak, and it is clear that susceptibility is also affected by other, as yet undiscovered loci.…”