Nine (10%) out of 90 hepatitis C virus (HCV) isolates from hepatitis patients and commercial blood donors in Thailand were not classifiable into any of genotypes I/1a, II/1b, III/2a, IV/2b, V/3a or VI/3b by RT-PCR with type-specific primers deduced from the HCV core gene. These isolates were sequenced over a 1.6 kb stretch of the 5′-terminal sequence and 1.1 kb of the 3′-terminal sequence covering 30% of the entire genome. Based on two-by-two comparison and phylogenetic analyses of the nine Thailand isolates among themselves and with known full or partial sequences of previously reported HCV isolates, the Thailand isolates were classified into five genotypes not reported previously, viz. 6b, 7c, 7d, 9b and 9c. Along with HCV isolates reported already, they make at least nine major genetic groups of HCV which further break down into at least 28 genotypes with sequence similarity in the E1 gene (576 bp) of ⩽80%. As many more HCV isolates of distinct genotypes are expected to be found throughout the world, it will become increasingly difficult to classify them by comparison of any partial sequences of the genome. Complete sequence data will be required for the full characterization and classification of HCV genotypes.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error