19-38500655-G-T

Variant names:

• chr19-38500655-G-T
• rs121918594
• NM_000540.3:c.7373G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1_Supporting PS4_Moderate PM5 PP3_Moderate

This summary comes from the ClinGen Evidence Repository: This pathogenicity assessment is relevant only for malignant hyperthermia susceptibility (MHS) inherited in an autosomal dominant pattern. Variants in RYR1 can also cause other myopathies inherited in an autosomal dominant pattern or in an autosomal recessive pattern. Some of these disorders may predispose individuals to malignant hyperthermia. RYR1 variants may also contribute to a malignant hyperthermia reaction in combination with other genetic and non-genetic factors and the clinician needs to consider such factors in making management decisions.This sequence variant predicts a substitution of arginine with leucine at codon 2458 of the RYR1 protein, p.(Arg2458Leu). This variant was not present in a large population database (gnomAD) at the time this variant was interpreted. This variant has been reported in two unrelated individuals who have a personal or family history of a malignant hyperthermia reaction, two of these individuals had a positive in vitro contracture test (IVCT) or caffeine halothane contracture test (CHCT) result (if the proband was unavailable for testing, a positive diagnostic test result in a mutation-positive relative was counted), PS4_Moderate (PMID:21965348, PMID:30236257). No functional studies were identified for this variant. This variant resides in a region of RYR1 considered to be a hotspot for pathogenic variants that contribute to MHS, use PM1_Supporting to avoid overweighting with PM5 (PMID:21118704). Another variant that has been assessed as pathogenic occurs at this codon, p.(Arg2458His), PM5. A REVEL score >0.85 (0.968) supports a pathogenic status for this variant, PP3_Moderate. This variant has been classified as Likely Pathogenic. Criteria implemented: PS4_Moderate, PM1_Supporting, PM5, PP3_Moderate. LINK:https://erepo.genome.network/evrepo/ui/classification/CA405670033/MONDO:0007783/012

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: RYR1 NM_000540.3 missense
• Clinical Significance: Likely pathogenic reviewed by expert panel P:2
• Conservation: PhyloP100: 9.99
• Publications: 21 publications found

Genes affected

RYR1 (HGNC:10483): (ryanodine receptor 1) This gene encodes a ryanodine receptor found in skeletal muscle. The encoded protein functions as a calcium release channel in the sarcoplasmic reticulum but also serves to connect the sarcoplasmic reticulum and transverse tubule. Mutations in this gene are associated with malignant hyperthermia susceptibility, central core disease, and minicore myopathy with external ophthalmoplegia. Alternatively spliced transcripts encoding different isoforms have been described. [provided by RefSeq, Jul 2008]

RYR1 Gene-Disease associations (from GenCC):

• malignant hyperthermia, susceptibility to, 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp, Ambry Genetics
• congenital multicore myopathy with external ophthalmoplegia

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp
• RYR1-related myopathy

  Inheritance: AR, AD Classification: DEFINITIVE Submitted by: ClinGen
• central core myopathy

  Inheritance: AD, AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp
• King-Denborough syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• malignant hyperthermia of anesthesia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• autosomal recessive centronuclear myopathy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• benign Samaritan congenital myopathy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• congenital myopathy with myasthenic-like onset

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• lethal multiple pterygium syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM1: For more information check the summary or visit ClinGen Evidence Repository.
• PM5: For more information check the summary or visit ClinGen Evidence Repository.
• PP3: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000540.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RYR1	NM_000540.3	MANE Select	c.7373G>T	p.Arg2458Leu	missense	Exon 46 of 106	NP_000531.2
	RYR1	NM_001042723.2		c.7373G>T	p.Arg2458Leu	missense	Exon 46 of 105	NP_001036188.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	RYR1	ENST00000359596.8	TSL:5 MANE Select	c.7373G>T	p.Arg2458Leu	missense	Exon 46 of 106	ENSP00000352608.2
	RYR1	ENST00000355481.8	TSL:1	c.7373G>T	p.Arg2458Leu	missense	Exon 46 of 105	ENSP00000347667.3
	RYR1	ENST00000594335.6	TSL:1	n.7373G>T		non_coding_transcript_exon	Exon 46 of 103	ENSP00000470927.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461666 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727118

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86246

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53338

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5670

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: reviewed by expert panel

Submissions by phenotype

Malignant hyperthermia, susceptibility to, 1 Pathogenic:1

Aug 01, 2025

ClinGen Malignant Hyperthermia Susceptibility Variant Curation Expert Panel, ClinGen

Significance: Likely pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

This pathogenicity assessment is relevant only for malignant hyperthermia susceptibility (MHS) inherited in an autosomal dominant pattern. Variants in RYR1 can also cause other myopathies inherited in an autosomal dominant pattern or in an autosomal recessive pattern. Some of these disorders may predispose individuals to malignant hyperthermia. RYR1 variants may also contribute to a malignant hyperthermia reaction in combination with other genetic and non-genetic factors and the clinician needs to consider such factors in making management decisions. This sequence variant predicts a substitution of arginine with leucine at codon 2458 of the RYR1 protein, p.(Arg2458Leu). This variant was not present in a large population database (gnomAD) at the time this variant was interpreted. This variant has been reported in two unrelated individuals who have a personal or family history of a malignant hyperthermia reaction, two of these individuals had a positive in vitro contracture test (IVCT) or caffeine halothane contracture test (CHCT) result (if the proband was unavailable for testing, a positive diagnostic test result in a mutation-positive relative was counted), PS4_Moderate (PMID:21965348, PMID:30236257). No functional studies were identified for this variant. This variant resides in a region of RYR1 considered to be a hotspot for pathogenic variants that contribute to MHS, use PM1_Supporting to avoid overweighting with PM5 (PMID: 21118704). Another variant that has been assessed as pathogenic occurs at this codon, p.(Arg2458His), PM5. A REVEL score >0.85 (0.968) supports a pathogenic status for this variant, PP3_Moderate. This variant has been classified as Likely Pathogenic. Criteria implemented: PS4_Moderate, PM1_Supporting, PM5, PP3_Moderate.

not provided Pathogenic:1

Aug 25, 2016

PreventionGenetics, part of Exact Sciences

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.87	D
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.71
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.72	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.6	M
PhyloP100		10
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-6.4	D
REVEL	Pathogenic	0.97
Sift	Uncertain	0.0010	D
Polyphen		1.0	D
Vest4		0.90
MutPred		0.81		Loss of MoRF binding (P = 0.0523)
MVP		1.0
MPC		0.38
ClinPred		1.0	D
GERP RS		4.0
Varity_R		0.71
gMVP		0.92
Mutation Taster		=2/98	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs121918594; hg19: chr19-38991295;