A meta-analysis evaluating the relationship between IL-18 gene promoter polymorphisms and an individual's susceptibility to HCV infection

Background : Several observational studies have investigated interleukin-18 (IL-18) gene polymorphisms with regard to suscepti- bility to hepatitis C virus (HCV) infection, but the results have been inconsistent. Aim : To evaluate the relationships between functional poly- morphisms in the IL-18 gene and an individual's susceptibility to HCV infection, a meta-analysis was performed. Methods: A literature search was conducted using the PubMed, EMBASE, Web of Science and China BioMedicine databases to investigate the correlation between IL-18 gene polymorphisms and susceptibility to HCV infection. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Results : The polymorphisms IL-18-607 C>A and -137 G>C were correlated with susceptibility to HCV infection in Asian populations. However, there was no evidence indicating a correlation between either of these polymorphisms and susceptibility to HCV infection in Caucasian populations. Conclusion : Our current meta-analysis suggests that the -607 C>A and -137 G>C polymorphisms in the IL-18 gene promoter play important roles in determining the response to HCV in Asian populations. More studies with larger sample sizes are needed to evaluate the associations between IL-18 genetic polymorphisms and HCV infection risk. (Acta Gastroenterol. belg., 2018, 81, 39-44).