These most accurate single gene markers that differentiated TB cases and contacts were BLR1, Bcl2, IL4d2, IL7R, FcgR1A, MARCO, MMP9, CCL19, and LTF with area under the curves (AUCs) of 0.84, 0.81, 0.79, 0.79, 0.78, 0.76, 0.75, 0.75 and 0.68, respectively (Figure 2). This evidence concerns the gene CCL19 and tuberculosis.