chr2-165994386-C-T

Variant names:

• chr2-165994386-C-T
• rs780360360
• NM_001165963.4:c.4612G>A

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 3P and 4B. PM1 PP2 BS2

The NM_001165963.4(SCN1A):​c.4612G>A​(p.Val1538Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000118 in 1,612,632 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V1538L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000033 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000096 (0 hom.)
• Consequence: SCN1A NM_001165963.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:6
• Conservation: PhyloP100: 4.86
• Publications: 4 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

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 12 uncertain in NM_001165963.4
• 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.
• BS2: High AC in GnomAd4 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN1A	NM_001165963.4	MANE Select	c.4612G>A	p.Val1538Ile	missense	Exon 28 of 29	NP_001159435.1
	SCN1A	NM_001202435.3		c.4612G>A	p.Val1538Ile	missense	Exon 27 of 28	NP_001189364.1
	SCN1A	NM_001353948.2		c.4612G>A	p.Val1538Ile	missense	Exon 26 of 27	NP_001340877.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN1A	ENST00000674923.1	MANE Select	c.4612G>A	p.Val1538Ile	missense	Exon 28 of 29	ENSP00000501589.1
	SCN1A	ENST00000303395.9	TSL:5	c.4612G>A	p.Val1538Ile	missense	Exon 27 of 28	ENSP00000303540.4
	SCN1A	ENST00000375405.7	TSL:5	c.4579G>A	p.Val1527Ile	missense	Exon 25 of 26	ENSP00000364554.3

Frequencies

GnomAD3 genomes AF: 0.0000329 AC: 5 AN: 151876 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000658

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: 0.00

GnomAD2 exomes AF: 0.0000200 AC: 5 AN: 249908 AF XY: 0.00000741

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000581

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000266

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000958 AC: 14 AN: 1460756 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 726662

African (AFR) AF: 0.00 AC: 0 AN: 33406

American (AMR) AF: 0.0000448 AC: 2 AN: 44620

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26096

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39634

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86214

European-Finnish (FIN) AF: 0.0000187 AC: 1 AN: 53386

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 0.00000810 AC: 9 AN: 1111334

Other (OTH) AF: 0.00 AC: 0 AN: 60316

GnomAD4 genome AF: 0.0000329 AC: 5 AN: 151876 Hom.: 0 Cov.: 32 AF XY: 0.0000270 AC XY: 2 AN XY: 74160

African (AFR) AF: 0.0000724 AC: 3 AN: 41408

American (AMR) AF: 0.0000658 AC: 1 AN: 15208

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5156

South Asian (SAS) AF: 0.00 AC: 0 AN: 4820

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10606

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

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67888

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.0000688 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.0000247 AC: 3

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	3	-	not provided (3)
1	-	-	Developmental and epileptic encephalopathy (1)
-	1	-	Generalized epilepsy with febrile seizures plus, type 2 (1)
-	1	-	Inborn genetic diseases (1)
-	1	-	Severe myoclonic epilepsy in infancy;C1858673:Generalized epilepsy with febrile seizures plus, type 2;C1864987:Migraine, familial hemiplegic, 3 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Pathogenic	0.18
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T
Eigen	Uncertain	0.65
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.65	D
MetaRNN	Uncertain	0.49	T
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Benign	1.4	L
PhyloP100		4.9
PrimateAI	Uncertain	0.69	T
PROVEAN	Benign	-0.83	N
REVEL	Uncertain	0.59
Sift	Benign	0.046	D
Sift4G	Benign	0.14	T
Polyphen		1.0	D
Vest4		0.42
MutPred		0.35		Gain of catalytic residue at V1538 (P = 0.1079)
MVP		0.96
MPC		1.5
ClinPred		0.33	T
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.18
gMVP		0.94
Mutation Taster		=0/100	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: rs780360360; hg19: chr2-166850896;