20-33408526-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_003098.3(SNTA1):c.1499G>A(p.Arg500His) variant causes a missense change. The variant allele was found at a frequency of 0.0000266 in 1,613,874 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. R500C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000027 (0 hom.)
• Consequence: SNTA1 NM_003098.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.90

Genes affected

SNTA1 (HGNC:11167): (syntrophin alpha 1) Syntrophins are cytoplasmic peripheral membrane scaffold proteins that are components of the dystrophin-associated protein complex. This gene is a member of the syntrophin gene family and encodes the most common syntrophin isoform found in cardiac tissues. The N-terminal PDZ domain of this syntrophin protein interacts with the C-terminus of the pore-forming alpha subunit (SCN5A) of the cardiac sodium channel Nav1.5. This protein also associates cardiac sodium channels with the nitric oxide synthase-PMCA4b (plasma membrane Ca-ATPase subtype 4b) complex in cardiomyocytes. This gene is a susceptibility locus for Long-QT syndrome (LQT) - an inherited disorder associated with sudden cardiac death from arrhythmia - and sudden infant death syndrome (SIDS). This protein also associates with dystrophin and dystrophin-related proteins at the neuromuscular junction and alters intracellular calcium ion levels in muscle tissue. [provided by RefSeq, Jan 2013]

LOC124904889 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• BS2: High AC in GnomAdExome at 8 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SNTA1	NM_003098.3	c.1499G>A	p.Arg500His	missense_variant	8/8	ENST00000217381.3
LOC124904889	XR_007067567.1	n.95-1527C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SNTA1	ENST00000217381.3	c.1499G>A	p.Arg500His	missense_variant	8/8	1	NM_003098.3	P1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152158 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000621

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000318 AC: 8 AN: 251344 Hom.: 0 AF XY: 0.0000515 AC XY: 7 AN XY: 135868

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: 0.000229

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000267 AC: 39 AN: 1461598 Hom.: 0 Cov.: 30 AF XY: 0.0000399 AC XY: 29 AN XY: 727110

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000220

Gnomad4 FIN exome AF: 0.0000187

Gnomad4 NFE exome AF: 0.0000144

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152276 Hom.: 0 Cov.: 32 AF XY: 0.0000403 AC XY: 3 AN XY: 74460

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000621

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ExAC AF: 0.0000576 AC: 7

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 09, 2022

The p.R500H variant (also known as c.1499G>A), located in coding exon 8 of the SNTA1 gene, results from a G to A substitution at nucleotide position 1499. The arginine at codon 500 is replaced by histidine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.56
BayesDel_addAF	Uncertain	0.074	D
BayesDel_noAF	Pathogenic	0.16
Cadd	Pathogenic	26
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.86	D
Eigen	Pathogenic	0.70
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.96	D
M_CAP	Uncertain	0.27	D
MetaRNN	Uncertain	0.72	D
MetaSVM	Uncertain	0.70	D
MutationAssessor	Uncertain	2.8	M
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-4.3	D
REVEL	Pathogenic	0.78
Sift	Uncertain	0.0070	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.61
MutPred		0.43		Loss of MoRF binding (P = 0.008);
MVP		0.95
MPC		1.1
ClinPred		0.92	D
GERP RS		4.5
Varity_R		0.43
gMVP		0.64

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: rs761509610; hg19: chr20-31996332; COSMIC: COSV54129310;