RYR1 mutations associated with malignant hyperthermia (MH) and CCD are grouped in three regions of RYR1 protein or ‘hot spots’: N-terminal (residues p.M1-R614), central (p.R2163–p.R2458) and C-terminal (p.R4136-p.P4973). The gene discussed is RYR1; the disease is Malignant hyperthermia.