IL12RB1 and Down syndrome: Genetic deficiencies in IL-12Rβ1, IFN-γR1, IL-12p40, STAT-1, IFN-γR2 or NEMO were traced back to a rare congenital syndrome, Mendelian susceptibility to mycobacterial diseases involving weakly virulent species [31] or to disseminated TB (IL-12Rβ1) [32].