Predicting sustained viral response to hepatitis C using a rapid and simple IL28B rs8099917 genotyping assay.

Recent studies showed that two single nucleotide polymorphisms (SNPs) (rs12979860 and rs8099917) near the gene IL28B coding for IFNλ3 were associated with the antiviral treatment response of the combination therapy of pegIFN plus RBV. We established the use of tetra-primer amplification refractory mutation system polymerase chain reaction (ARMS-PCR) for detecting IL28B rs8099917 genotype (T>G) in 56 Chinese chronic hepatitis C patients infected with Hepatitis C Virus (HCV) genotype 1. The new assay showed 98.2% specificity, and was confirmed by direct sequencing. Among the 56 samples, TT genotype and TG genotype accounted for 80.4% (45/56) and 19.6% (11/56), respectively. GG genotype was not found. The proportion of responders in TT group was higher than that in TG group (68.9% vs. 27.3%, p=0.029). For HCV clinical decision-making, using the new assay, rs8099917 genotyping could provide similar information to rs12979860 genotyping due to a strong association between the two SNPs in Chinese patients. The assay system in this study can be implemented using basic laboratory equipments, making it convenient for clinical and research purposes.