chr19-38444203-A-G

Variant names:

• chr19-38444203-A-G
• rs193922752
• NM_000540.3:c.479A>G

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PS4_Supporting PM1 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 glutamic acid with glycine at codon 160 of the RYR1 protein, p.(Glu160Gly). This variant was not present in a large population database (gnomAD) at the time it was interpreted. This variant has been reported in an individual who has a personal or family history of a malignant hyperthermia reaction, this individual 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_Supporting (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, PM1 (PMID:21118704). A REVEL score >0.85 (0.957) supports a pathogenic status for this variant, PP3_Moderate. Using Bayes to combine criteria this variant is assessed as a Variant of Uncertain Significance, (PMID:29300386). Criteria implemented: PS4_Supporting, PM1, PP3_Moderate. LINK:https://erepo.genome.network/evrepo/ui/classification/CA024462/MONDO:0007783/012

• Frequency: Genomes: not found (cov: 32)
• Consequence: RYR1 NM_000540.3 missense
• Clinical Significance: Uncertain significance reviewed by expert panel P:1 U:1 O:1
• Conservation: PhyloP100: 9.29
• Publications: 6 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: Uncertain_significance. The variant received 5 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.
• 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.479A>G	p.Glu160Gly	missense	Exon 6 of 106	NP_000531.2
	RYR1	NM_001042723.2		c.479A>G	p.Glu160Gly	missense	Exon 6 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.479A>G	p.Glu160Gly	missense	Exon 6 of 106	ENSP00000352608.2
	RYR1	ENST00000355481.8	TSL:1	c.479A>G	p.Glu160Gly	missense	Exon 6 of 105	ENSP00000347667.3
	RYR1	ENST00000594335.6	TSL:1	n.479A>G		non_coding_transcript_exon	Exon 6 of 103	ENSP00000470927.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

RYR1-related disorder Pathogenic:1

Feb 10, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense change has been observed in individuals with central core disease and/or malignant hyperthermia susceptibility (PMID: 14985404, 21674524, 30236257; Invitae). For these reasons, this variant has been classified as Pathogenic. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt RYR1 protein function. ClinVar contains an entry for this variant (Variation ID: 133136). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 160 of the RYR1 protein (p.Glu160Gly).

Malignant hyperthermia, susceptibility to, 1 Uncertain:1

Aug 01, 2025

ClinGen Malignant Hyperthermia Susceptibility Variant Curation Expert Panel, ClinGen

Significance: Uncertain significance

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 glutamic acid with glycine at codon 160 of the RYR1 protein, p.(Glu160Gly). This variant was not present in a large population database (gnomAD) at the time it was interpreted. This variant has been reported in an individual who has a personal or family history of a malignant hyperthermia reaction, this individual 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_Supporting (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, PM1 (PMID: 21118704). A REVEL score >0.85 (0.957) supports a pathogenic status for this variant, PP3_Moderate. Using Bayes to combine criteria this variant is assessed as a Variant of Uncertain Significance, (PMID: 29300386). Criteria implemented: PS4_Supporting, PM1, PP3_Moderate.

not provided Other:1

RYR1 database

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.50
CADD	Uncertain	26
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.92	D
Eigen	Pathogenic	0.73
Eigen_PC	Uncertain	0.63
FATHMM_MKL	Uncertain	0.82	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.73	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.0	M
PhyloP100		9.3
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-5.4	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.72
MutPred		0.83		Gain of MoRF binding (P = 0.0836)
MVP		0.99
MPC		0.98
ClinPred		1.0	D
GERP RS		4.3
Varity_R		0.79
gMVP		0.95
Mutation Taster		=1/99	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs193922752; hg19: chr19-38934843;