Mg2+ supplementation can restore NKG2D surface expression and EBV specific immune control in some of these patients (Chaigne-Delalande et al., 2013), but has not proven to be a successful durable therapy of XMEN (Ravell et al., 2020b). The gene discussed is KLRK1; the disease is X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection and neoplasia.