rs193922749

chr19-38440851-C-Achr19-38440851-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PP2 PP3_Moderate

The NM_000540.3(RYR1):c.152C>A(p.Thr51Asn) variant causes a missense change. The variant allele was found at a frequency of 0.000146 in 1,611,932 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T51I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00015 (0 hom.)
• Consequence: RYR1 NM_000540.3 missense
• Clinical Significance: Uncertain significance reviewed by expert panel U:6 B:1 O:1
• Conservation: PhyloP100: 6.03

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000540.3
• PP2: Missense variant where missense usually causes diseases, RYR1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.898

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RYR1	NM_000540.3	c.152C>A	p.Thr51Asn	missense_variant	2/106	ENST00000359596.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RYR1	ENST00000359596.8	c.152C>A	p.Thr51Asn	missense_variant	2/106	5	NM_000540.3	A2
RYR1	ENST00000355481.8	c.152C>A	p.Thr51Asn	missense_variant	2/105	1		P4
RYR1	ENST00000599547.6	c.152C>A	p.Thr51Asn	missense_variant, NMD_transcript_variant	2/80	2

Frequencies

GnomAD3 genomes AF: 0.0000657 AC: 10 AN: 152190 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000132

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000534 AC: 13 AN: 243498 Hom.: 0 AF XY: 0.0000527 AC XY: 7 AN XY: 132752

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000119

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000154 AC: 225 AN: 1459742 Hom.: 0 Cov.: 31 AF XY: 0.000143 AC XY: 104 AN XY: 726102

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.000184

Gnomad4 OTH exome AF: 0.000331

GnomAD4 genome AF: 0.0000657 AC: 10 AN: 152190 Hom.: 0 Cov.: 32 AF XY: 0.0000673 AC XY: 5 AN XY: 74344

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000132

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000818 Hom.: 0

Bravo AF: 0.0000529

ExAC AF: 0.0000412 AC: 5

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6 Benign:1 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

Malignant hyperthermia, susceptibility to, 1 Uncertain:2 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Oct 04, 2017	This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -
Uncertain significance, reviewed by expert panel	curation	ClinGen Malignant Hyperthermia Susceptibility Variant Curation Expert Panel, ClinGen	Apr 06, 2023	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 Threonine with Asparagine at codon 51 of the RYR1 protein, p.(Thr51Asn). The maximum allele frequency for this variant among the six major gnomAD populations is NFE: 0.00012 (15 alleles), a frequency consistent with pathogenicity for MHS. This variant has been reported in an individual with a personal or family history of an MH episode and 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), (PMID:18564801 ). However, the high MAF in the NFE population in gnomAD precludes the use of PS4. 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).This variant segregates with MHS in 1 individual (PMID:18564801). A REVEL score of 0.769 supports neither a pathogenic nor a benign status for this variant. This variant has been classified as a Variant of Unknown Significance. Criteria implemented: PM1. -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Dec 13, 2023	This missense variant replaces threonine with asparagine at codon 51 of the RYR1 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). Although functional studies have not been reported for this variant, it occurs in a region of RYR1 considered to be a hotspot for pathogenic variants that contribute to malignant hyperthermia susceptibility (PMID: 21118704). This variant has been reported in an individual affected with malignant hyperthermia susceptibility with a personal history of a malignant hyperthermia episode (PMID: 18564801). This variant has been identified in 15/274886 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

not provided Uncertain:2 Other:1

Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Apr 30, 2014	- -
not provided, no classification provided	literature only	Leiden Muscular Dystrophy (RYR1)	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Jun 30, 2020	- -

Congenital multicore myopathy with external ophthalmoplegia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Oct 04, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

RYR1-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 01, 2022

This sequence change replaces threonine, which is neutral and polar, with asparagine, which is neutral and polar, at codon 51 of the RYR1 protein (p.Thr51Asn). This variant is present in population databases (rs193922749, gnomAD 0.01%). This missense change has been observed in individual(s) with malignant hyperthermia susceptibility (PMID: 18564801). ClinVar contains an entry for this variant (Variation ID: 133099). 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. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.68
BayesDel_addAF	Uncertain	0.044	T
BayesDel_noAF	Uncertain	0.030
Cadd	Uncertain	24
Dann	Uncertain	0.99
Eigen	Pathogenic	0.69
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.87	D
MetaRNN	Pathogenic	0.90	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.6	M;M
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Uncertain	-3.4	D;D
REVEL	Pathogenic	0.77
Sift	Uncertain	0.0060	D;D
Polyphen		1.0	D;D
Vest4		0.66
MVP		1.0
MPC		1.1
ClinPred		0.84	D
GERP RS		4.8
Varity_R		0.54
gMVP		0.65

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

Publications

LitVar

Other links and lift over

dbSNP: rs193922749; hg19: chr19-38931491;