What are the different genotypes of hepatitis C, and why are they important?

Oil painting of the molecular structure of the Hepatitis C virus

There are seven major genotypes of hepatitis C (HCV), numbered 1-7, and several subtypes. Genotypes are important because they:

1. Determine treatment duration and regimen: Different genotypes respond better to specific treatment combinations and durations.
2. Influence treatment outcome: Some genotypes are more resistant to treatment than others.
3. Affect disease progression: Genotype 3 is associated with faster liver damage progression.
4. Impact liver cancer risk: Genotype 3 is linked to a higher risk of liver cancer.
5. Guide treatment decisions: Genotyping helps healthcare providers choose the most effective treatment approach.