2-165991619-G-T

Variant names:

• chr2-165991619-G-T
• rs779614747
• NM_001165963.4:c.5656C>A
• SCN1A p.Arg1886Arg

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP6

The NM_001165963.4(SCN1A):​c.5656C>A​(p.Arg1886Arg) variant causes a synonymous change. The variant allele was found at a frequency of 0.00000205 in 1,461,716 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 Conflicting classifications of pathogenicity (no stars). The gene SCN1A is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SCN1A NM_001165963.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:2
• Conservation: PhyloP100: 3.65
• Publications: 6 publications found

Genes affected

SCN1A (HGNC:10585): (sodium voltage-gated channel alpha subunit 1) Voltage-dependent sodium channels are heteromeric complexes that regulate sodium exchange between intracellular and extracellular spaces and are essential for the generation and propagation of action potentials in muscle cells and neurons. Each sodium channel is composed of a large pore-forming, glycosylated alpha subunit and two smaller beta subunits. This gene encodes a sodium channel alpha subunit, which has four homologous domains, each of which contains six transmembrane regions. Allelic variants of this gene are associated with generalized epilepsy with febrile seizures and epileptic encephalopathy. Alternative splicing results in multiple transcript variants. The RefSeq Project has decided to create four representative RefSeq records. Three of the transcript variants are supported by experimental evidence and the fourth contains alternate 5' untranslated exons, the exact combination of which have not been experimentally confirmed for the full-length transcript. [provided by RefSeq, Oct 2015]

SCN1A-AS1 (HGNC:54069): (SCN1A and SCN9A antisense RNA 1)

LOC102724058 (HGNC:):

ACMG classification

Specifications for SCN1A are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.49).
• BP6: Variant 2-165991619-G-T is Benign according to our data. Variant chr2-165991619-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 682297.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001165963.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN1A	NM_001165963.4	MANE Select	c.5656C>A	p.Arg1886Arg	synonymous	Exon 29 of 29	NP_001159435.1	P35498-1
	SCN1A	NM_001202435.3		c.5656C>A	p.Arg1886Arg	synonymous	Exon 28 of 28	NP_001189364.1	P35498-1
	SCN1A	NM_001353948.2		c.5656C>A	p.Arg1886Arg	synonymous	Exon 27 of 27	NP_001340877.1	P35498-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN1A	ENST00000674923.1	MANE Select	c.5656C>A	p.Arg1886Arg	synonymous	Exon 29 of 29	ENSP00000501589.1	P35498-1
	SCN1A	ENST00000303395.9	TSL:5	c.5656C>A	p.Arg1886Arg	synonymous	Exon 28 of 28	ENSP00000303540.4	P35498-1
	SCN1A	ENST00000375405.7	TSL:5	c.5623C>A	p.Arg1875Arg	synonymous	Exon 26 of 26	ENSP00000364554.3	P35498-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000798 AC: 2 AN: 250570 AF XY: 0.0000148

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000177

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461716 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727158

African (AFR) AF: 0.00 AC: 0 AN: 33464

American (AMR) AF: 0.00 AC: 0 AN: 44698

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26130

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111902

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

EpiCase AF: 0.000109

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	Early-infantile DEE (1)
-	1	-	Generalized epilepsy with febrile seizures plus, type 2 (1)
-	1	-	Migraine, familial hemiplegic, 3 (1)
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.49
CADD	Benign	8.9
DANN	Benign	0.66
PhyloP100		3.6
Mutation Taster		=100/0	polymorphism

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs779614747;

hg19: chr2-166848129;