In support of this explanation, CD4+ T cells from HIV-1 controllers with higher A3G expression levels were found to be more resistant to HIV-1 infection in vitro compared with CD4+ T cells from HIV-1 controllers with lower A3G expression levels (Biasin et al., 2007; De Pasquale et al., 2013). The gene discussed is CD4; the disease is HIV-1 infection.