Consensus Proposals for a Uniﬁed System of
Nomenclature of Hepatitis C Virus Genotypes
Donald G. Murphy,
Lieven J. Stuyver,
Amy J. Weiner,
and Anders Widell
International standardization and coordination of the nomenclature of variants of hepatitis
C virus (HCV) is increasingly needed as more is discovered about the scale of HCV-related
liver disease and important biological and antigenic differences that exist between variants.
A group of scientists expert in the ﬁeld of HCV genetic variability, and those involved in
development of HCV sequence databases, the Hepatitis Virus Database (Japan), euHCVdb
(France), and Los Alamos (United States), met to re-examine the status of HCV genotype
nomenclature, resolve conﬂicting genotype or subtype names among described variants of
HCV, and draw up revised criteria for the assignment of new genotypes as they are discov-
ered in the future. A comprehensive listing of all currently classiﬁed variants of HCV
incorporates a number of agreed genotype and subtype name reassignments to create con-
sistency in nomenclature. The paper also contains consensus proposals for the classiﬁcation
of new variants into genotypes and subtypes, which recognizes and incorporates new knowl-
edge of HCV genetic diversity and epidemiology. A proposal was made that HCV variants be
classiﬁed into 6 genotypes (representing the 6 genetic groups deﬁned by phylogenetic anal-
ysis). Subtype name assignment will be either conﬁrmed or provisional, depending on the
availability of complete or partial nucleotide sequence data, or remain unassigned where
fewer than 3 examples of a new subtype have been described. In conclusion, these proposals
provide the framework by which the HCV databases store and provide access to data on
HCV, which will internationally coordinate the assignment of new genotypes and subtypes
in the future.
Abbreviations: HCV, hepatitis C virus; IDU, injection drug user; RF, recombinant form; ICTV, International Committee for the Taxonomy of Viruses.
Centre for Infectious Diseases, University of Edinburgh, Summerhall, Edinburgh, United Kingdom;
Hepatitis Viruses Section, Laboratory of Infectious
Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD;
Institut de Biologie et Chimie des Prote´ines, Poˆle
BIoinformatique de Lyon, BioSciences Lyon-Gerland, Lyon, France;
First Department of Internal Medicine, University of Yamanashi, Tamaho, Yamanashi, Japan;
Laboratory of Hepatitis Viruses, Division of Viral Products, Food and Drug Administration, Bethesda, MD;
Laboratoire Alphabio, Marseille, France;
BioMe´rieux, Immunothe´rapie des Maladies Infectieuses Chroniques, Lyon, France;
Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los
Innogenetics n.v., Ghent, Belgium;
Department of Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical
Sciences, Kawasumi, Mizuho, Nagoya, Japan;
Laboratoire de Sante´ Publique du Que´bec, Institut National de Sante´ Publique du Que´bec, Que´bec, Canada;
of Virology, Department of Infection and Immunity, Jichi Medical School, Tochigi, Japan;
Department of Virology, INSERM U635, Henri Mondor Hospital, University
of Paris, Cre´teil, France;
Virco BVBA, Generaal De Wittelaan, Mechelen, Belgium;
Institut fu¨r Virologie, Justus-Liebig-Universita¨t, Giessen, Germany;
Virology, Essen University Hospital, Essen, Germany;
Chiron Corporation, Emeryville, CA; and the
Department of Medical Microbiology, Malmo¨ University Hospital,
Lund University, Malmo¨, Sweden.
Received April 21, 2005; accepted June 2, 2005.
The European HCV database is funded by HepCVax Cluster (EU FP5 grant QLK2-2002-01329) and VIRGIL Network of Excellence (EU FP6 grant LSHM-CT-
Address reprint requests to: Peter Simmonds, Centre for Infectious Diseases, University of Edinburgh, Summerhall, Edinburgh, EH9 1QH, United Kingdom. E-mail:
Peter.Simmonds@ed.ac.uk; fax: (44) 131 650 6511.
Copyright © 2005 by the American Association for the Study of Liver Diseases.
Published online in Wiley InterScience (www.interscience.wiley.com).
Potential conﬂict of interest: Nothing to report.