Hepatitis C virus genotype 7, a new genotype originating from central Africa

Abstract

We report a new hepatitis C virus (HCV) genotype identified in patients originating from the Democratic Republic of Congo. The prototype QC69 virus is shown to be a new lineage distinct from genotypes 1 to 6. Three additional patients were also found to be infected by a virus from this lineage, confirming its circulation in humans. We propose that these viruses be classified into HCV genotype 7.

FIG 1

Genomic representation and organization of isolate QC69. The positions of 13 PCR fragments used to determine the full-length sequence are indicated.

FIG 2

Maximum-likelihood phylogeny of nucleotide sequences for the complete coding region of representatives of the seven genotypes of HCV. Genotypes 1 to 4 and 6 are each represented by 10 genomes, including two of the same subtype. The major branches corresponding to each genotype are indicated within the tree. The numbers adjacent to the branch nodes represent the percent bootstrap robustness for 100 replicates; values of ≥70% are shown. Sequences are labeled to the right of each branch in order as follows: genotype/subtype, isolate identification, and GenBank accession number. Bar, nucleotide substitutions per site.

FIG 3

Maximum-likelihood phylogeny of NS5B sequences corresponding to positions 8276 to 8615 (340 bp) of representatives of the seven genotypes of HCV. The phylogeny was reconstructed using NS5B sequences of genomes included in Fig. 1 and of isolates QC272, IG93306, and IG93305. The major branches corresponding to each genotype are indicated within the tree. The numbers adjacent to the branch nodes represent the percent bootstrap robustness for 1,000 replicates; values of ≥70% are shown. Sequences are labeled to the right of each branch in order as follows: genotype/subtype, isolate identification, and GenBank accession number. Bar, nucleotide substitutions per site.