Analysis of 5' non-coding region in hepatitis C virus by single-strand conformation polymorphism and low-stringency...

Area of Science:

• Virology
• Molecular Biology
• Genetics

Background:

• Hepatitis C virus (HCV) genotyping is crucial for patient management and treatment.
• Accurate and reliable methods are needed for differentiating HCV genotypes and mixed infections.

Purpose of the Study:

• To evaluate the informativeness and reliability of Single-strand conformation polymorphism (SSCP) and low-stringency single specific primer (LSSP)-PCR for HCV genotyping.
• To assess the utility of these methods in identifying mixed HCV infections.

Main Methods:

• SSCP and LSSP-PCR were applied to the 5' non-coding region of 14 HCV isolates (7 type 1, 2 type 2, 2 type 3, and 5 mixed infections).
• Direct cycle sequencing was used to determine sequence divergences and confirm genotypes.
• Optimized conditions were established for SSCP and LSSP-PCR analyses.

Main Results:

• Optimized SSCP clearly distinguished between HCV genotypes 1, 2, and 3, and detected intra-genotype variants.
• SSCP and DNA sequencing failed to confirm mixed HCV infections.
• LSSP-PCR successfully differentiated between genotypes 1, 2, and 3 but not intra-genotype variants.
• LSSP-PCR profiles distinctly identified isolates with mixed HCV infections.

Conclusions:

• SSCP is a reliable method for HCV genotyping and detecting sequence variants within genotypes.
• LSSP-PCR is a novel and effective method for differentiating HCV genotypes and, importantly, for identifying mixed infections.
• LSSP-PCR offers a significant advantage in diagnosing complex HCV infections.