Interferon lambda 4 gene polymorphisms as a predicting tool of response to hepatitis C virus genotype 4 patients treated with Sofosbuvir and Ribavirin

The relation between interferon lambda 4 gene (IFNL4) and direct acting antiviral (DAA) regimens in hepatitis C virus (HCV) infected patients is not clear. So, a single nucleotide polymorphisms (SNP) of IFNL4 gene genotypes and its relationship with Sofosbuvir (SOF) and Ribavirin (RBV) treatment response is under consideration. This study aims to investigate the relation between IFNL4 polymorphisms and clearance of HCV genotype 4 for HCV patients. Hence, the appropriate drug can be chosen for each patient. SNP genotyping assay for IFNL4 which formerly known as IL28B (rs368234815) was examined for genomic DNA. The DNA was extracted from whole blood of one hundred patients who documented to have infection with chronic HCV genotype 4 (positive PCR) and treated with SOF and RBV. Patients were diagnosed, previously, as HCV genotype 4 and classified according to drug response into two groups (responders, non-responders). All samples were compared with 50 of non-infected (negative PCR) people (control group). The TT/TT homozygous represents 48% of patients and 66% of non-infected people while the homozygous ∆G/∆G is 21% and 12%, respectively. There is significance to IFNL4 genotypes for the treatment response with the probability value p < 0.001. The percentages of the appearance of genotypes TT/TT, TT/∆G and ∆G/∆G for responders were 60%, 28% and 12%, respectively. There is no significance for gender, age, ALT and PLC to treatment response to SOF and RBV, while INR has.