- Exclusion of defects in the skeletal muscle specific regions of the DHPR alpha 1 subunit as frequent causes of malignant hyperthermia. O'Brien, R.O., Taske, N.L., Hansbro, P.M., Matthaei, K.I., Hogan, S.P., Denborough, M.A., Foster, P.S. J. Med. Genet. (1995)