Identification of numerous hepatitis C virus genotypes in Montreal, Canada.

Hepatitis C virus genotypes were determined for 358 viremic individuals in Montreal, Canada, by restriction endonuclease analysis of PCR products and phylogenetic analysis of core gene sequences. Types 1, 2, and 3 occurred in 62.8, 14.2, and 13.7%, respectively; types 4 and 5 were found in 3.9 and 4.5%, respectively; and genotypes 6a and 7c and a novel genotype each occurred in 0.3%. Types 4, 6, and 7 and the novel genotype were mostly from persons who had immigrated to Canada.