To identify the step in HIV-1 infection that was impaired in THP-1 cells lacking SUN2 expression, we infected control cells and SUN2 knockout g3c4 cells with DNase-treated VSV-G-pseudotyped NL4.3GFP and isolated total DNA at 6 or 24 h after infection for use in a TaqMan quantiative PCR (qPCR). The gene discussed is SUN2; the disease is infection.