- The G1021A substitution in the RYR1 gene does not cosegregate with malignant hyperthermia susceptibility in a British pedigree. Adeokun, A.M., West, S.P., Ellis, F.R., Halsall, P.J., Hopkins, P.M., Foroughmand, A.M., Iles, D.E., Robinson, R.L., Stewart, A.D., Curran, J.L. Am. J. Hum. Genet. (1997)