IDO1 and leprosy: As for differentiating leprosy per se vs. ODD, genes IDO1, BLK (exon 11), CD38, CXCL11, and SLAMF7, all had an area under the curve (AUC) of at least 96% with their lower bound 97% confidence intervals above 90% (Figs 2A, 3C and S6 Table).