The cross-sensitivity patterns of the mutant were examined for covalently (anthramycin) and non-covalently (distamycin A) binding minor groove ligands, and DNA intercalating [adriamycin, mitoxantrone and 4'-(9-acridinylamino)methanesulphon-m-anisidide (mAMSA)] and non-intercalating (VP16-213) topoisomerase II poisons.