The genes that encode the NOX2 complex in phagocytes are related to chronic granulomatous disease [51,52]: CYBB pathogenic variants cause X-linked recessive chronic granulomatous disease (CGDX, [53]) and immunodeficiency 34 [54]), CYBA pathogenic variants cause autosomal recessive (AR) CGD4 [55], NCF1 pathogenic variants cause AR CGD1 [56], NCF2 pathogenic variants cause AR CGD2 [57], and NCF4 pathogenic variants cause AR CGD3 [58] (Table 1). This evidence concerns the gene NCF4 and immune system disorder.