Transmitted HIV-1 tends to access more prevalent sequence space than matched chronic viruses.

Amino acid substitution (or variation) frequencies for sites that exhibit amino acid divergence between the matched TF/CC pairs are shown using between 4568 sequences (Tat) and 19237 sequences (Nef) for subtype B and between 1548 sequences (Rev) and 4345 sequences (Env) for subtype C using sequences from the Los Alamos sequence database for each viral protein. Each point represents one of the amino acid sites that differs between the TF and CC in that virus pair. Medians and interquartile ranges are indicated and significance was determined using a Mann-Whitney test.