Partial nonstructural 3 region analysis of hepatitis C virus genotype 3a

Area of Science:

• Virology
• Molecular Biology
• Drug Discovery

Background:

• Hepatitis C virus (HCV) infection remains a global health concern.
• HCV genotype 3a is prevalent in Thailand, necessitating targeted treatment strategies.
• Direct-acting antivirals (DAAs) target HCV NS3, NS5A, and NS5b proteins, but resistance mutations emerge.

Purpose of the Study:

• To analyze codon positions of key mutations in the NS3 gene region of HCV genotype 3a.
• To investigate naturally occurring and treatment-induced resistance mutations in HCV NS3.
• To identify common mutation sites within the NS3 gene of prevalent Thai HCV strains.

Main Methods:

• Nucleotide sequencing and amino acid analysis of the NS3 gene region.
• Detection and confirmation of HCV genotype 3a.
• Clustering of sequenced samples into defined sub-clades (3a-1 and 3a-2).

Main Results:

• Twenty-six HCV genotype 3a samples were successfully sequenced.
• Amino acid variations were identified at multiple codon positions: 122 (3.8%), 132 (84.6%), 168 (100%), 170 (92.3%), 174 (100%), and 175 (100%).
• High prevalence of mutations at positions 168, 170, 174, and 175 was observed.

Conclusions:

• Mutations at NS3 positions 168, 170, 174, and 175 are frequently observed in HCV genotype 3a.
• Understanding these common mutations is crucial for designing effective DAAs.
• This research contributes to the development of improved therapies for HCV infection.