rs749326085

Variant names:

• chr2-165293848-G-A
• rs749326085
• NM_001040142.2:c.-51-1925G>A

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_001040142.2(SCN2A):​c.-51-1925G>A variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000609 in 984,778 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 28)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: SCN2A NM_001040142.2 intron
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.11
• Publications: 0 publications found

Genes affected

SCN2A (HGNC:10588): (sodium voltage-gated channel alpha subunit 2) Voltage-gated sodium channels are transmembrane glycoprotein complexes composed of a large alpha subunit with four repeat domains, each of which is composed of six membrane-spanning segments, and one or more regulatory beta subunits. Voltage-gated sodium channels function in the generation and propagation of action potentials in neurons and muscle. This gene encodes one member of the sodium channel alpha subunit gene family. Allelic variants of this gene are associated with seizure disorders and autism spectrum disorder. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2016]

SCN2A Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Illumina
• developmental and epileptic encephalopathy, 11

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• intellectual disability

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• episodic ataxia, type 9

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• seizures, benign familial infantile, 3

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• benign familial infantile epilepsy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• benign familial neonatal-infantile seizures

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Dravet syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• genetic developmental and epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• malignant migrating partial seizures of infancy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.68).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN2A	NM_001040142.2	c.-51-1925G>A		intron_variant	Intron 1 of 26	ENST00000375437.7	NP_001035232.1
SCN2A	NM_001371246.1	c.-51-1925G>A		intron_variant	Intron 1 of 26	ENST00000631182.3	NP_001358175.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN2A	ENST00000375437.7	c.-51-1925G>A		intron_variant	Intron 1 of 26	5	NM_001040142.2	ENSP00000364586.2
SCN2A	ENST00000631182.3	c.-51-1925G>A		intron_variant	Intron 1 of 26	5	NM_001371246.1	ENSP00000486885.1
SCN2A	ENST00000424833.5	c.-51-1925G>A		intron_variant	Intron 1 of 10	1		ENSP00000406454.2
SCN2A	ENST00000283256.10	c.-339G>A		upstream_gene_variant		1		ENSP00000283256.6

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 151668 Hom.: 0 Cov.: 28

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: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.000479

GnomAD4 exome AF: 0.00000480 AC: 4 AN: 833110 Hom.: 0 Cov.: 29 AF XY: 0.00000520 AC XY: 2 AN XY: 384714

African (AFR) AF: 0.00 AC: 0 AN: 15786

American (AMR) AF: 0.00 AC: 0 AN: 984

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 5152

East Asian (EAS) AF: 0.00 AC: 0 AN: 3630

South Asian (SAS) AF: 0.00 AC: 0 AN: 16460

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 276

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 1620

European-Non Finnish (NFE) AF: 0.00000394 AC: 3 AN: 761904

Other (OTH) AF: 0.0000366 AC: 1 AN: 27298

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 151668 Hom.: 0 Cov.: 28 AF XY: 0.0000270 AC XY: 2 AN XY: 74046

African (AFR) AF: 0.00 AC: 0 AN: 41268

American (AMR) AF: 0.00 AC: 0 AN: 15228

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5150

South Asian (SAS) AF: 0.00 AC: 0 AN: 4804

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10502

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67934

Other (OTH) AF: 0.000479 AC: 1 AN: 2086

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Seizures, benign familial infantile, 3 Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.68
CADD	Benign	4.1
DANN	Benign	0.82
PhyloP100		-1.1
PromoterAI		-0.028	Neutral

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: rs749326085; hg19: chr2-166150358;