INHA and tuberculosis: We used multiple M/XDR-TB isolates to test for an association between MIC levels and mutations and found a significant association of the inhA promoter -15 c/t, embB Gly406Asp, gid mutations, gryA Ala90Val and rpoB Asp435Phe/Tyr/Val with low MIC levels spanning the CCs for INH, EMB, STR, MXF and RFB, respectively.