Impact of IFNL4 Genetic Variants on Sustained Virologic Response and Viremia in Hepatitis C Virus Genotype 3 Patients

Area of Science:

• Genetics
• Virology
• Immunology

Background:

• Hepatitis C virus (HCV) genotype 3 is common in Europe and Asia, linked to poorer outcomes.
• Genetic factors are implicated in HCV infection, but genome-wide studies are lacking for genotype 3.
• Understanding genetic influences can optimize treatment strategies.

Purpose of the Study:

• To investigate the role of genetic variants in HCV genotype 3 patients.
• To analyze associations with response to interferon (IFN) and direct-acting antiviral (DAA) regimens.
• To explore the impact on viral load (viremia).

Main Methods:

• A large cohort of 1,759 HCV genotype 3 patients was studied.
• Combined candidate gene and genome-wide association analyses were performed.
• The functional dinucleotide polymorphism rs368234815 in the IFNL4 locus was specifically examined.

Main Results:

• Genetic variants in the IFNL4 gene were major factors associated with treatment response and viremia.
• rs368234815 showed significant association with IFN-based sustained virologic response (SVR).
• This variant also impacted viremia and direct-acting antiviral (DAA)-based SVR.

Conclusions:

• Genetic variants, particularly at the IFNL4 locus, play a role in HCV genotype 3 viremia.
• These genetic factors influence both IFN-based and direct-acting antiviral (DAA)-based treatment outcomes.
• Findings highlight the importance of host genetics in managing HCV genotype 3 infections.