chr2-166046818-T-C

Variant names:

• chr2-166046818-T-C
• rs1553546728
• NM_001165963.4:c.1329A>G

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 2P and 10B. PM2 BP4_Strong BP6 BP7 BS2

The NM_001165963.4(SCN1A):​c.1329A>G​(p.Glu443Glu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,594 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).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: SCN1A NM_001165963.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 0.657
• Publications: 0 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)

ACMG classification

Our verdict: Benign. The variant received -8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.58).
• BP6: Variant 2-166046818-T-C is Benign according to our data. Variant chr2-166046818-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 448246.
• BP7: Synonymous conserved (PhyloP=0.657 with no splicing effect.
• BS2: High AC in GnomAdExome4 at 5 AD,Unknown gene.

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.1329A>G	p.Glu443Glu	synonymous	Exon 12 of 29	NP_001159435.1	P35498-1
	SCN1A	NM_001202435.3		c.1329A>G	p.Glu443Glu	synonymous	Exon 11 of 28	NP_001189364.1	P35498-1
	SCN1A	NM_001353948.2		c.1329A>G	p.Glu443Glu	synonymous	Exon 10 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.1329A>G	p.Glu443Glu	synonymous	Exon 12 of 29	ENSP00000501589.1	P35498-1
	SCN1A	ENST00000303395.9	TSL:5	c.1329A>G	p.Glu443Glu	synonymous	Exon 11 of 28	ENSP00000303540.4	P35498-1
	SCN1A	ENST00000375405.7	TSL:5	c.1329A>G	p.Glu443Glu	synonymous	Exon 9 of 26	ENSP00000364554.3	P35498-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461594 Hom.: 0 Cov.: 32 AF XY: 0.00000413 AC XY: 3 AN XY: 727084

African (AFR) AF: 0.00 AC: 0 AN: 33452

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00000450 AC: 5 AN: 1111802

Other (OTH) AF: 0.00 AC: 0 AN: 60378

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000468 Hom.: 0

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	Developmental and epileptic encephalopathy (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.58
CADD	Benign	7.7
DANN	Benign	0.67
PhyloP100		0.66
Mutation Taster		=99/1	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

Other links and lift over

dbSNP: rs1553546728; hg19: chr2-166903328;