Interaction Analysis of Genetic Variation at Il12a and IL12B with Chronic Hepatitis B

Hepatitis B virus (HBV) infection is a major cause of chronic liver diseases worldwide. Cytokines are important in immune responses, with T-helper1 (Th1) cytokines aiding in viral clearance through cell-mediated immunity. Interleukin-12 (IL-12) plays a critical role in regulating the secretion of IFN-y by Th1 cells and natural killer cells. Mutations in cytokine genes, like IL-12 composed of p35 and p40 chains, can impact protein production in HBV-infected hepatic cells. This study aims to explore how IL12A and IL12B genotypes affect the development of chronic hepatitis B. A total of 380 patients, 340 healthy controls, and 123 healthy individuals who had recovered from HBV infection were included in the study. Polymorphisms at positions -1148T/C (rs2243123) and 277G/A (rs568408) in the IL-12A gene, as well as rs6887695G/C in the IL-12B gene, were analyzed using the polymerase chain reaction-restriction fragment length polymorphism method. The frequencies of rs568408 genotypes in HBV patients were GG (70.5%), AG (27.9%), AA (1.6%), in healthy controls GG (70%), AG (26.5%), AA (3.5%), and in the cleared group GG (73.2%), AG (24.4%), AA (2.4%) with a p-value of 0.505. The frequencies of -1148TT, TC, and CC genotypes in the chronic HBV group were 71.6, 25.5, and 2.9%, in the healthy group 65, 28.8, and 6.2%, and in the cleared group 65, 28.3, and 6.5%, with a p-value of 0.129. The frequencies of rs6887695 genotypes in HBV patients, healthy controls, and the cleared group for GG were 53.9, 37.9, and 8.7%, for GC 37.9, 45.3, and 45.3%, and for CC 8.7, 8.2, and 8.1% (p = 0.256). This study is the first to investigate the role of genetic polymorphisms (rs2243123, rs2243123, and rs6887695) of IL12A and IL12B genes in the development of chronic hepatitis B in the Iranian population.