chr1-237500770-A-T

Variant names:

• chr1-237500770-A-T
• rs1553474585
• NM_001035.3:c.2263A>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP2

The NM_001035.3(RYR2):​c.2263A>T​(p.Ile755Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,684 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. I755V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: RYR2 NM_001035.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.82
• Publications: 0 publications found

Genes affected

RYR2 (HGNC:10484): (ryanodine receptor 2) This gene encodes a ryanodine receptor found in cardiac muscle sarcoplasmic reticulum. The encoded protein is one of the components of a calcium channel, composed of a tetramer of the ryanodine receptor proteins and a tetramer of FK506 binding protein 1B proteins, that supplies calcium to cardiac muscle. Mutations in this gene are associated with stress-induced polymorphic ventricular tachycardia and arrhythmogenic right ventricular dysplasia. [provided by RefSeq, Jul 2008]

RYR2 Gene-Disease associations (from GenCC):

• arrhythmogenic right ventricular dysplasia 2

  Inheritance: AD Classification: DEFINITIVE, NO_KNOWN Submitted by: Laboratory for Molecular Medicine, Ambry Genetics
• catecholaminergic polymorphic ventricular tachycardia

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen, G2P
• catecholaminergic polymorphic ventricular tachycardia 1

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the RYR2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 195 curated pathogenic missense variants (we use a threshold of 10). The gene has 55 curated benign missense variants. Gene score misZ: 5.7809 (above the threshold of 3.09). Trascript score misZ: 6.4158 (above the threshold of 3.09). GenCC associations: The gene is linked to hypertrophic cardiomyopathy, catecholaminergic polymorphic ventricular tachycardia 1, catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular dysplasia 2, arrhythmogenic right ventricular cardiomyopathy.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RYR2	NM_001035.3	c.2263A>T	p.Ile755Phe	missense_variant	Exon 21 of 105	ENST00000366574.7	NP_001026.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RYR2	ENST00000366574.7	c.2263A>T	p.Ile755Phe	missense_variant	Exon 21 of 105	1	NM_001035.3	ENSP00000355533.2
RYR2	ENST00000661330.2	c.2263A>T	p.Ile755Phe	missense_variant	Exon 21 of 106			ENSP00000499393.2
RYR2	ENST00000609119.2	n.2263A>T		non_coding_transcript_exon_variant	Exon 21 of 104	5		ENSP00000499659.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461684 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727118

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111852

Other (OTH) AF: 0.00 AC: 0 AN: 60374

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Catecholaminergic polymorphic ventricular tachycardia 1 Uncertain:1

Sep 18, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. 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 not expected to disrupt RYR2 protein function. This variant has not been reported in the literature in individuals affected with RYR2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces isoleucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 755 of the RYR2 protein (p.Ile755Phe). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.74
BayesDel_addAF	Uncertain	0.052	T
BayesDel_noAF	Benign	-0.16
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.84	D;T
Eigen	Uncertain	0.60
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Uncertain	0.97	D;D
M_CAP	Uncertain	0.25	D
MetaRNN	Uncertain	0.68	D;D
MetaSVM	Uncertain	-0.23	T
MutationAssessor	Uncertain	2.8	M;.
PhyloP100		2.8
PrimateAI	Uncertain	0.68	T
PROVEAN	Uncertain	-3.3	D;.
REVEL	Uncertain	0.59
Sift	Uncertain	0.0010	D;.
Polyphen		0.97	D;.
Vest4		0.83
MutPred		0.64		Loss of sheet (P = 0.3635);.;
MVP		0.64
MPC		0.74
ClinPred		0.98	D
GERP RS		4.7
Varity_R		0.53
gMVP		0.83
Mutation Taster		=26/74	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs1553474585; hg19: chr1-237664070;