2-165090164-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_006922.4(SCN3A):c.5989G>T(p.Glu1997Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000698 in 1,431,954 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: SCN3A NM_006922.4 stop_gained
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.41

Genes affected

SCN3A (HGNC:10590): (sodium voltage-gated channel alpha subunit 3) Voltage-gated sodium channels are transmembrane glycoprotein complexes composed of a large alpha subunit with 24 transmembrane domains and one or more regulatory beta subunits. They are responsible for the generation and propagation of action potentials in neurons and muscle. This gene encodes one member of the sodium channel alpha subunit gene family, and is found in a cluster of five alpha subunit genes on chromosome 2. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

(HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.00233 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SCN3A	NM_006922.4	c.5989G>T	p.Glu1997Ter	stop_gained	28/28	ENST00000283254.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SCN3A	ENST00000283254.12	c.5989G>T	p.Glu1997Ter	stop_gained	28/28	1	NM_006922.4	P1
	ENST00000638199.1	n.1144-956C>A		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.98e-7 AC: 1 AN: 1431954 Hom.: 0 Cov.: 29 AF XY: 0.00000141 AC XY: 1 AN XY: 709966

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: 0.0000120

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 25, 2022

Not observed at significant frequency in large population cohorts (gnomAD); Nonsense variant predicted to result in protein truncation as the last 4 amino acids are lost, although loss-of-function variants have not been reported downstream of this position in the protein; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.66
Cadd	Pathogenic	38
Dann	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Uncertain	0.91	D
MutationTaster	Benign	0.99	D;D;D;D
Vest4		0.45
GERP RS		6.0

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: rs1342543734; hg19: chr2-165946674; COSMIC: COSV51823256; COSMIC: COSV51823256;