Genetic polymorphism in IFNL4 and response to pegylated interferon-α and ribavirin in Japanese chronic hepatitis C patients.

A genetic polymorphism of the newly discovered interferon-λ 4 ( IFNL4) gene was associated with hepatitis C virus ( HCV) clearance in individuals of African ancestry. To assess whether a dinucleotide variant of IFNL4 (ss469415590) also affected treatment outcome of antiviral therapy in Japan, we genotyped 213 patients with chronic genotype 1 HCV infection and 176 healthy subjects. The ΔG allele was associated with treatment failure [odds ratio ( OR) 4.73, P = 0.019], as was the IFL3 rs8099917 single nucleotide polymorphism ( SNP) ( OR 5.06, P = 0.068). The correlation between ss469415590 and rs8099917 was high ( r2 = 0.92, D′ = 0.98). Multivariate analysis revealed that the rs8099917 SNP was independently associated with treatment failure ( OR 5.28, P = 0.009). Therefore, ss469415590 may be another predictive marker of antiviral therapy outcome in the Japanese population. [ABSTRACT FROM AUTHOR]