Fig. 1

a Phylogenetic analysis of Hepatitis C virus (HCV) isolates. Consensus sequences of an 857 nucleotide (nt) fragment of the HCV NS3 protease from the three HCV isolates from the cohort were aligned with the Los Alamos National Laboratory HCV Database consensus sequences for HCV genotype (gt) 1a and 3a, along with additional reference sequences from subjects living in Los Angeles, to make a neighbor-joining tree. The consensus sequences for gt 1a and 3a are labeled as “CON” with the corresponding genotype. The Los Angeles HCV sequences are labeled as “LA” with the corresponding subject number. The HCV-positive subject samples are labeled A, B, and C. The tree is rooted with the HCV genotype 1a consensus sequence and the genetic distance scale bar is located at the center of the figure. b Phylogenetic analysis of HIV-1 pol. A 1302 nt fragment of pol covering the HIV-1 protease and reverse transcriptase (HXB2 reference location nt 2254–3555) from N = 148 isolates from the cohort was aligned with the Clade B consensus and used to build a neighbor-joining tree. Each sequence is labeled with a unique subject identifier, and the HCV-positive subjects are labeled A, B, and C. The tree is rooted with the Clade B consensus sequence. The genetic distance scale bar is located at the lower left of the figure