IL23A and tuberculosis: Another study reported that in haplotypes of IL12RB1 gene “allele 2” R214-T365-R378 and “ATGG” haplotype of (641A/G, 1094T/C, 1132C/G, 1573G/A) associate with TB susceptibility in the Japanese population and this variation may diminish receptor response to IL-12 and IL-23 which may lead to downregulation of IFN-γ mediated immunity (165, 166).