To confirm that Env-CCR5 interaction contributes to HIV-1 bystander pathogenesis in a relevant HIV-1 infection model in vivo, we compared the infection and pathogenesis of R3A with R3A-5/6AA in the huHSC mice, a suitable small animal model to study HIV pathogenesis in vivo [22]. The gene discussed is ERVW-1; the disease is HIV-1 infection.