Mutations in seven autosomal (IFNGR1, IFNGR2, IL12B, IL12RB1, STAT1, IRF8, ISG15) and two X-linked (NEMO, CYBB) genes have since been identified in patients with MSDM [29–33], which all result in impaired IFN-γ mediated immunity to infection [23]. Here, IFNG is linked to infection.