2-165090206-T-A

Variant names:

• chr2-165090206-T-A
• rs774354894
• NM_006922.4:c.5947A>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_006922.4(SCN3A):​c.5947A>T​(p.Lys1983*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. K1983K) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SCN3A NM_006922.4 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.36
• Publications: 0 publications found

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]

SCN3A Gene-Disease associations (from GenCC):

• genetic developmental and epileptic encephalopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: Illumina, ClinGen
• developmental and epileptic encephalopathy, 62

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• epilepsy, familial focal, with variable foci 4

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• undetermined early-onset epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000236283 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 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 0.00933 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 rank	MANE	Protein	UniProt
SCN3A	NM_006922.4	c.5947A>T	p.Lys1983*	stop_gained	Exon 28 of 28	ENST00000283254.12	NP_008853.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN3A	ENST00000283254.12	c.5947A>T	p.Lys1983*	stop_gained	Exon 28 of 28	1	NM_006922.4	ENSP00000283254.7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.61	D
BayesDel_noAF	Pathogenic	0.63
CADD	Pathogenic	38
DANN	Uncertain	0.99
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		3.4
Vest4		0.61
GERP RS		6.0
Mutation Taster		=44/156	disease causing

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: rs774354894; hg19: chr2-165946716;