Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Hepatitis C virus (HCV) shows considerable variation in its genomic structure, allowing classification into six main genotypes. Epidemiological studies have shown marked differences in genotype distribution by geographical region, and between patient groups. Improved understanding of the rate of nucleotide sequence mutation in HCV has allowed the approximate time of divergence of major genotypes to be estimated, and the origin and spread of the present epidemic of hepatitis C to be better defined. Improved methods of genotype definition over the last few years have enabled the importance of genotype in the progression of HCV-related disease and response to anti-viral therapy to be studied. Present data strongly indicates that HCV genotype is an important determinant of response to treatment, but the effect of genotype on disease progression has been harder to clarify. This is largely due to the absence of model systems of HCV infection, the epidemiological differences in patient groups infected with the different genotypes, and the lack of good prospective longitudinal clinical data. As a result of advances in methodology, and recent results of large clinical trials of combination therapy, a knowledge of HCV genotype is now central to the clinician in the management of patients with chronic hepatitis C.

Original publication




Journal article


Bailliere's best practice & research. Clinical gastroenterology

Publication Date





229 - 240


Centre for Hepatology, Department of Medicine, Royal Free and University College Medical School, London, UK.


Humans, Hepacivirus, Hepatitis C, Interferon Type I, Recombinant Proteins, RNA, Viral, Ribavirin, Antiviral Agents, Incidence, Genotype, Global Health