2-166073501-T-C

Variant names:

• chr2-166073501-T-C
• rs764444350
• NM_001165963.4:c.121A>G

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_001165963.4(SCN1A):​c.121A>G​(p.Lys41Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). The gene SCN1A is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SCN1A NM_001165963.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.27
• Publications: 2 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

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

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the SCN1A gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 848 curated pathogenic missense variants (we use a threshold of 10). The gene has 89 curated benign missense variants. Gene score misZ: 5.2206 (above the threshold of 3.09). Trascript score misZ: 7.6022 (above the threshold of 3.09). GenCC associations: The gene is linked to generalized epilepsy with febrile seizures plus, type 2, developmental and epileptic encephalopathy, 6A, familial hemiplegic migraine, generalized epilepsy with febrile seizures plus, Lennox-Gastaut syndrome, malignant migrating partial seizures of infancy, Dravet syndrome, myoclonic-astatic epilepsy, familial or sporadic hemiplegic migraine, migraine, familial hemiplegic, 3, genetic developmental and epileptic encephalopathy, arthrogryposis.
• BP4: Computational evidence support a benign effect (MetaRNN=0.15615848).

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.121A>G	p.Lys41Glu	missense	Exon 4 of 29	NP_001159435.1	P35498-1
	SCN1A	NM_001202435.3		c.121A>G	p.Lys41Glu	missense	Exon 3 of 28	NP_001189364.1	P35498-1
	SCN1A	NM_001353948.2		c.121A>G	p.Lys41Glu	missense	Exon 2 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.121A>G	p.Lys41Glu	missense	Exon 4 of 29	ENSP00000501589.1	P35498-1
	SCN1A	ENST00000303395.9	TSL:5	c.121A>G	p.Lys41Glu	missense	Exon 3 of 28	ENSP00000303540.4	P35498-1
	SCN1A	ENST00000375405.7	TSL:5	c.121A>G	p.Lys41Glu	missense	Exon 1 of 26	ENSP00000364554.3	P35498-2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251458 AF XY: 0.00000736

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461880 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727240

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.0000545

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.084
BayesDel_addAF	Uncertain	0.083	D
BayesDel_noAF	Benign	-0.12
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.34	T
Eigen	Benign	-0.092
Eigen_PC	Benign	0.11
FATHMM_MKL	Benign	0.73	D
LIST_S2	Benign	0.73	T
M_CAP	Benign	0.040	D
MetaRNN	Benign	0.16	T
MetaSVM	Uncertain	-0.094	T
MutationAssessor	Benign	1.5	L
PhyloP100		2.3
PrimateAI	Uncertain	0.53	T
PROVEAN	Benign	-0.98	N
REVEL	Benign	0.26
Sift	Uncertain	0.023	D
Sift4G	Benign	0.25	T
Polyphen		0.0010	B
Vest4		0.24
MutPred		0.23		Loss of ubiquitination at K41 (P = 0.0255)
MVP		0.61
MPC		1.0
ClinPred		0.22	T
GERP RS		5.8
PromoterAI		0.038	Neutral
Varity_R		0.15
gMVP		0.57
Mutation Taster		=45/55	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: rs764444350; hg19: chr2-166930011;