Abstract: The present invention relates to methods of identifying, collecting and isolating pluripotent stem cells, and compositions of purified stem cells for the diagnosis of susceptibility to drug induced myopathy (DIM) and malignant hyperthermia (MH). Specifically, the present invention provides methods of producing skeletal muscle myocytes from patient-specific stem cells, and methods for identifying susceptibility to DIM and MH in patient-specific skeletal muscle myocytes generated from patient-specific stem cells. The present invention also relates to methods, compositions and kits for screening drugs for DIM and MH risk.