As, in contrast to adaptive NKG2C+ NK cells26, a large fraction of naive NKG2C+ NK cells coexpress NKG2A (Extended Data Fig. 5g,h), these data suggest that peptide recognition might be decisive in biasing the pool of naive NKG2C+ cells recruited during HCMV infection toward NKG2A−NKG2C+ cells. Here, KLRC2 is linked to cytomegalovirus infection.