Clinically relevant sequence-based genotyping of HBV, HCV, CMV, and HIV

Area of Science:

• Virology
• Genetics
• Molecular Biology

Background:

• Genotyping, or genetic characterization of a genome, identifies mutations differentiating individuals or strains.
• These mutations can confer drug resistance or aid in strain classification.
• Genotype information is clinically useful for four human viruses: Hepatitis B virus (HBV), Hepatitis C virus (HCV), cytomegalovirus (CMV), and human immunodeficiency virus type 1 (HIV-1).

Purpose of the Study:

• To review the clinical utility of genotyping for specific human viruses.
• To highlight the role of genotypic analysis in managing antiviral drug resistance and treatment regimens.
• To discuss the current state and methods of viral genotyping in clinical virology.

Main Methods:

• Review of existing literature on viral genotyping and its clinical applications.
• Discussion of genotypic analysis as a method for detecting drug resistance mutations.
• Comparison of different genotyping approaches, including sequence-based methods.

Main Results:

• Genotyping is essential for detecting antiviral drug resistance in HBV due to its inability to be cultured.
• HCV genotyping guides treatment duration, impacting therapeutic regimens and managing side effects.
• Genotyping assays, particularly for the UL97 gene, aid in managing CMV disease and identifying resistance.
• HIV-1 genotyping is a standard of care, essential for guiding antiretroviral therapy by identifying resistance mutations in protease and reverse transcriptase genes.

Conclusions:

• Genotyping is a critical tool in clinical virology for personalized medicine, particularly in managing viral infections and optimizing treatment strategies.
• While sequence-based methods are the gold standard, other genotyping approaches are valuable for routine clinical use.
• Accurate viral genotyping directly impacts patient outcomes by enabling targeted therapies and effective management of drug resistance.