CYBB and chronic granulomatous disease: There are exceptions to all of these depending on the molecular defects, for example both AD and AR forms of IFNGR1 deficiency leading to Mendelian susceptibility to mycobacterial disease (MSMD) [8], or female carriers of CYBB variants associated with XL chronic granulomatous disease (CGD) having infectious susceptibility and/or autoimmunity due to non-random X-chromosome inactivation [9].