These studies indeed show a high viremia state for more than 3 months and a gradual decrease in the number of human CD4+ T cells in HIV-1-infected humanized NOG or Rag2−/−γC−/− mice [23]–[26], the production of both anti-HIV-1 Env gp120- and Gag p24-specific antibodies in humanized NOG mice with a high rate of HIV-1 infection [27], the role of Treg cells in the maintenance of high levels of HIV-1 infection in HIV-1-infected humanized Rag2−/−γC−/− mice [28], and the selection of mutations by APOBEC3 in the HIV genome in humanized NOG mice [29]. The gene discussed is CD4; the disease is HIV-1 infection.