SARS-CoV-2 infected-patients develop specific antibodies, CD4+ T cells, and CD8+ T cells in response to the infection (3, 6, 8, 9), although, CD4+ T cells had the strongest association with diminished COVID-19 disease severity compared with the other two arms (B cells, CD8+ T cells) of the adaptive immunity (6). The gene discussed is CD4; the disease is infection.