A single-nucleotide polymorphism of IL12A gene (rs582537 A/C/G) and susceptibility to chronic hepatitis B virus infection among Iraqi patients

A case–control study (80 patients with chronic hepatitis B virus [HBV] infection and 96 controls) was performed to evaluate the association of an IL12A gene variant (rs582537 A/C/G) with HBV infection. Allele G showed a significantly lower frequency in patients compared to controls (31.2 vs . 46.9%; probability [ p ] = 0.009; corrected p [ pc ] = 0.027) and was associated with a lower risk of HBV infection (odds ratio [OR] = 0.49; 95% confidence interval [CI] = 0.29–0.83). A similar lower risk was associated with genotypes CG (17.5 vs . 29.2; OR = 0.25; 95% CI = 0.08–0.81; p = 0.02) and GG (10.0 vs . 16.7; OR = 0.25; 95% CI = 0.07–0.91; p = 0.036), but the pc value was not significant (0.12 and 0.126, respectively). Serum IL-35 levels showed significant differences between individuals of different genotypes ( p = 0.007). The highest median was associated with CA genotype (286.5 pg/mL), followed by genotypes CG (227.0 pg/mL), GG (206.5 pg/mL), CC (169.0 pg/mL), AA (137.5 pg/mL) and finally AG (125.0 pg/mL). In conclusion, rs582537 appears to be an important genetic variant that may influence not only susceptibility to HBV infection but IL-35 levels.