In the primary X-linked immunodeficiency with magnesium defect, the Epstein-Barr virus infection, and neoplasia (XMEN), magnesium transporter 1 (MAGT1) is mutated and the diminished intracellular magnesium levels compromise glycosylation and surface expression of NKG2D [88]. Here, MAGT1 is linked to X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection and neoplasia.