Phylogenetic reconstruction of HCV E1/E2 region sequences from 5 plasma donors (10081, 10051, 10082, 10017, and 10022) and a chimpanzee (X355) infused with a pool of 50 mL of plasma from each of the donors. ▴ indicates population sequences corresponding to the first hypervariable region (HVR-1) of E1/E2 (404nt) for donors and the chimp; and ▵, cloned sequences. Samples from 2 time points 19 days apart were obtained from the chimpanzee. The first time point sequences are indicated with c and the second time point sequences by C. Viral sequences in the chimp are shown to be closely related to donor 10081. Reference sequences from genotypes 1a (HCV-H, H77, and HCV-1), 1b (L2, JK1), and 3a (K3a) were included. The maximum likelihood tree was rooted with the 3a reference sequence. Bootstrap values > 70% are indicated.