Fewer unique sequences of HCV subtype 2b (Panel A) than 1a (Panel B) were identified at UWHC. A) DNA sequence of the 5' UTR of the discordant 2b/1a strain is aligned with several representative non-discordant 2b strains, as well as the 5' UTR of the prototypical 1a H77 strain. These 8 sequences represent all the sequence diversity of this region of the 14 2b subtypes found in the 12 months in which both the 5' UTR and NS5B regions were sequenced. B) Alignment of the NS5B protein and nucleotide sequence of the 2b/1a discordant strain with three typical 1a strains as well as a 2b reference strain. NS5B DNA sequence of isolate A is quite close to the 2b/1a strain, but the NS5B DNA sequences of isolates B and C are less similar, yet more typical of 1a strains from UWHC, with 3 identical sequences from the 90 subtype 1a sequences determined in the 12 month period.