In addition, there is some evidence that HIV-1 is adapting its codon use to better suit the host’s tRNA pool; e.g. Meintjes and Rodrigo[59] analysed partial env gene sequences from 8 HIV-1 infected patients over time (from seroconversion till the AIDS phase) and found that codon use in later env genes was more similar to that of the host than that in early samples. Here, ERVW-1 is linked to AIDS.