Diversification of hepatitis C viruses in South America reveals a novel genetic lineage

Hepatitis C virus (HCV) has high genomic variability and, since its discove ry, at least six different types and an increasing number of sub-types have been reported. Genotype 1 is the most prevalent genotype found in South Am erica. Recent phylogenetic analysis of strains isolated in Uruguay revealed the presence of a different genetic lineage from major sub-types 1a and 1b . In order to study if type 1 HCV strains circulating in the South American region can be associated with this genetic lineage, sequence data obtained from the 5' non-coding region from 6 type 1 patients from Chile, were comp ared with sequences obtained from 12 type 1 Uruguayan and 9 type 1 Brazilia n patients as well as 17 different strains of all types isolated elsewhere. The phylogenetic analysis revealed the existence of type 1 strains of this novel genetic lineage in all South American countries studied, and indicat es a diversification of HCV viruses in the South American region.