Two IL28B polymorphisms are associated with the treatment response of different genotypes of hepatitis C in different racial populations: A meta-analysis.

The purpose of this present meta-analysis is to provide an accurate estimation of the association between two IL28B polymorphisms (rs8099917 and rs12979860) and sustained virological response (SVR) to standard treatment of patients of different racial descent infected with different genotypes of hepatitis C virus (HCV), and also to investigate the possible factors in the IL28B gene that contribute to the different SVR rates of patients with different subtypes of HCV infection across different populations. The electronic database PubMed was searched. Asian patients with a common homozygote (TT vs. TG/GG, OR=3.17; CC vs. CT/TT, OR=3.75) attained a higher rate of SVR, and a similar result was observed in European patients (TT vs. TG/GG, OR=1.74; CC vs. CT/TT, OR=2.50). Furthermore, HCV1-infected patients with a common homozygote (TT vs. TG/GG, OR=2.95; CC vs. CT/TT, OR=4.34) appeared to have a higher SVR rate than those with HCV2/3 (TT vs. TG/GG, OR=1.56; CC vs. CT/TT, OR=1.37). The frequency of the common homozygote in Asian patients was high, followed by European patients and African patients. In all, Asian patients attained a higher SVR rate than European patients (P<0.05). Patients with HCV1 infection had a lower SVR rate than those with HCV2/3 infection (P<0.001). Our results suggest that both the common allele frequency and racial descent itself contribute to the difference in SVR rates across different population groups, and the common allele frequency may partly elucidate the different SVR rates in patients with different genotypes of HCV.