Three Type 6 Hepatitis C Virus Subgroups among Blood Donors in the Yangon Area of Myanmar Are Identified as Subtypes 6m and 6n, and a Novel Subtype by Sequence Analysis of the Core Region.

Previously, using phylogenetic analysis of NS5b sequences, we found that three type 6 variant subgroups (M6-1, M6-2 and M6-3) exist in Myanmar. According to the new nomenclature of hepatitis C, M6-1 and M6-2 belong to subtypes 6m and 6n, respectively, but M6-3 is unassigned. In this study, we sequenced and phylogenetically analyzed the core region of these type 6 variant subgroups. Serum samples assigned as 6m or 6n by NS5b sequence were also identifi ed as 6 m or 6n by core region analysis. The M6-3 (sample name MYAN-3E-3) remained unassigned to a subgroup based on its core region analysis. The fi ndings of this study suggest that either the core region or the NS5b region can be analyzed for HCV subtype classifi cation.