Mutations that cause CGD are found in CYBB and CYBA, which encode the membrane-bound NADPH oxidase components Nox2/gp91phox and p22phox, and NCF1, NCF2, and NCF4, which encode the cytosolic regulatory factors p47phox, p67phox, and p40phox, respectively (Figure 1) (O'Neill et al., 2015). This evidence concerns the gene CYBA and chronic granulomatous disease.