In the case of 70-0710-1, the absence of any WB bands at 18 months followed by the appearance of p24 and p55 Gag bands at 21 months coincided with cytomegalovirus infection, which strongly activates the immune system and lowers CD4/CD8 ratios32 (Extended Data Fig. 4b). The gene discussed is CD4; the disease is cytomegalovirus infection.