Table 1.

Summary of characteristics of the patients contributing samples for this study. The RYR1 variants are annotated for their likely pathogenicity using the criteria of Miller and colleaguesl⁶ as: *unlikely pathogenic; †potentially pathogenic; ^‡likely pathogenic; and ^¶pathogenic. In vitro contracture testing (IVCT) data for each MHS individual is available in Supplementary Table S1. MHN, malignant hyperthermia-negative; MHS, malignant hyperthermia-susceptible; MHS_h, abnormal response in the in vitro contracture test to halothane but not caffeine; MHS_hc, abnormal response in the in vitro contracture test to halothane and caffeine

	MHN (n=36)	MHS (n=23)
		MHSh (n=12)			MHShc (n=11)
Male:female	16:20	5:7			7:4
Age at biopsy (yr)	(11–68)	(12–64)			(12–57)
Individuals with at least one RYR1 variant	–	8			10
RYR1 variants found	–	Nucleotide change	Amino acid change	Accession number	Nucleotide change	Amino acid change	Accession number
		c.251C>T†	p.Thr84Met	rs186983396	c.455C>A†	p.Ala152Asp	–
		c.4178A>G*	p.Lys1393Arg	rs137933390	c.1202G>A‡	p.Arg401His	rs193922766
		c.5183C>T‡	p.Ser1728Phe	rs193922781	c.8729C>T†	p.Tyr2910Met	–
		c.6670C>T†	p.Arg2224Cys	rs199870223	c.10357C>T†	p.Arg3453Cys	rs1482429489
		c.6785G>A†	p.Gly2262Asp	–	c.11132C>T‡	p.Thr3711Met	rs375915752
		c.7879G>A‡	p.Val2627Met	–	c.11958C>G‡	p.Asp3986Glu	rs193922842
		c.12860C>T†	p.Ala4287Val	–	c.12700G>C‡	p.Val4234Leu	rs193922852
		c.14210G>Ac	p.Arg4737Gln	rs193922868	c.7879G>A‡	p.Val2627Met	–
		c.4293G>A	p.Thr1431=	rs727504130	c.1021G>A¶	p.Gly341Arg	rs121918592