Genetic Variant SCN1A:p.Val1589Ala (chr2-165994232-A-G) – ACMG Classification: Likely_pathogenic (9 pts)

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1PM2PM5PP2PP3_Moderate

The NM_001165963.4(SCN1A):c.4766T>C(p.Val1589Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,862 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V1589L) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

SCN1A
NM_001165963.4 missense

Scores

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 7.36

Publications

1 publications found

Variant links:

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 links:

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

SCN1A-AS1 links:

LOC102724058 (HGNC:):

LOC102724058 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

PM1

In a hotspot region, there are 15 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_001165963.4

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr2-165994232-A-C is described in ClinVar as Pathogenic. ClinVar VariationId is 189998.Status of the report is criteria_provided_single_submitter, 1 stars.

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 familial or sporadic hemiplegic migraine, myoclonic-astatic epilepsy, arthrogryposis, Dravet syndrome, malignant migrating partial seizures of infancy, generalized epilepsy with febrile seizures plus, type 2, migraine, familial hemiplegic, 3, developmental and epileptic encephalopathy, 6A, familial hemiplegic migraine, generalized epilepsy with febrile seizures plus, genetic developmental and epileptic encephalopathy, Lennox-Gastaut syndrome.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.892

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

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
SCN1A	NM_001165963.4	MANE Select	c.4766T>C	p.Val1589Ala	missense	Exon 28 of 29	NP_001159435.1
SCN1A	NM_001202435.3		c.4766T>C	p.Val1589Ala	missense	Exon 27 of 28	NP_001189364.1
SCN1A	NM_001353948.2		c.4766T>C	p.Val1589Ala	missense	Exon 26 of 27	NP_001340877.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
SCN1A	ENST00000674923.1	MANE Select	c.4766T>C	p.Val1589Ala	missense	Exon 28 of 29	ENSP00000501589.1
SCN1A	ENST00000303395.9	TSL:5	c.4766T>C	p.Val1589Ala	missense	Exon 27 of 28	ENSP00000303540.4
SCN1A	ENST00000375405.7	TSL:5	c.4733T>C	p.Val1578Ala	missense	Exon 25 of 26	ENSP00000364554.3

Frequencies

GnomAD3 genomes

Cov.:

GnomAD2 exomes

AF:

0.00000399

AC:

AN:

250444

AF XY:

0.00000739

show subpopulations

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:

0.00000884

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.85e-7

AC:

AN:

1460862

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726740

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33424

American (AMR)

AF:

0.00

AC:

AN:

44620

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26114

East Asian (EAS)

AF:

0.00

AC:

AN:

39634

South Asian (SAS)

AF:

0.00

AC:

AN:

86214

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53370

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5758

European-Non Finnish (NFE)

AF:

9.00e-7

AC:

AN:

1111404

Other (OTH)

AF:

0.00

AC:

AN:

60324

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.475

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

Cov.:

Alfa

AF:

0.00

Hom.:

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.19

BayesDel_addAF

Pathogenic

0.30

BayesDel_noAF

Pathogenic

0.19

CADD

Uncertain

(source)

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.96

Eigen

Uncertain

0.63

Eigen_PC

Pathogenic

0.67

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.72

M_CAP

Pathogenic

0.65

MetaRNN

Pathogenic

0.89

MetaSVM

Pathogenic

1.1

MutationAssessor

Benign

1.6

PhyloP100

7.4

PrimateAI

Uncertain

0.77

PROVEAN

Uncertain

-3.0

REVEL

Pathogenic

0.82

Sift

Uncertain

0.0040

Sift4G

Uncertain

0.0020

Polyphen

1.0

Vest4

0.61

MutPred

0.72

Gain of ubiquitination at K1591 (P = 0.0856)

MVP

0.92

MPC

1.3

ClinPred

0.92

GERP RS

5.9

Varity_R

0.27

gMVP

0.97

Mutation Taster

=2/98

disease causing

(source)

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

ClinVar

Computational scores

Splicing

Publications

Other links and lift over