rs794726698

Variant names:

• chr2-165992272-G-A
• NM_001165963.4:c.5003C>T

Your query was ambiguous. Multiple possible variants found:

• chr2-165992272-G-A
• chr2-165992272-G-C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PS1_Moderate PM1 PM2 PP2 PP3_Strong

The NM_001165963.4(SCN1A):​c.5003C>T​(p.Pro1668Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in UniProt.

• Frequency: Genomes: not found (cov: 31)
• Consequence: SCN1A NM_001165963.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.82

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

Verdict is Pathogenic. Variant got 11 ACMG points.

• PS1: Transcript NM_001165963.4 (SCN1A) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in UniProt
• PM1: In a repeat IV (size 298) in uniprot entity SCN1A_HUMAN there are 62 pathogenic changes around while only 3 benign (95%) in NM_001165963.4
• 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 migraine, familial hemiplegic, 3, familial hemiplegic migraine, Dravet syndrome, malignant migrating partial seizures of infancy, generalized epilepsy with febrile seizures plus, myoclonic-astatic epilepsy, developmental and epileptic encephalopathy, developmental and epileptic encephalopathy, 6, familial or sporadic hemiplegic migraine, arthrogryposis, Lennox-Gastaut syndrome, generalized epilepsy with febrile seizures plus, type 2.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.943

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN1A	NM_001165963.4	c.5003C>T	p.Pro1668Leu	missense_variant	Exon 29 of 29	ENST00000674923.1	NP_001159435.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN1A	ENST00000674923.1	c.5003C>T	p.Pro1668Leu	missense_variant	Exon 29 of 29		NM_001165963.4	ENSP00000501589.1
SCN1A	ENST00000303395.9	c.5003C>T	p.Pro1668Leu	missense_variant	Exon 28 of 28	5		ENSP00000303540.4
SCN1A	ENST00000375405.7	c.4970C>T	p.Pro1657Leu	missense_variant	Exon 26 of 26	5		ENSP00000364554.3
SCN1A	ENST00000409050.1	c.4919C>T	p.Pro1640Leu	missense_variant	Exon 26 of 26	5		ENSP00000386312.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Severe myoclonic epilepsy in infancy Uncertain:1

-

Neuberg Centre For Genomic Medicine, NCGM

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The missense variant p.P1668L in SCN1A (NM_001165963.4) has not been reported previously as a pathogenic or a bening variant. Another change at the same amino acid residue has been previously established as a pathogenic variant (Huang W et al,2017). The p.P1668L variant is novel (not in any individuals) in gnomAD Exomes and is novel (not in any individuals) in 1000 Genomes. There is a moderate physicochemical difference between proline and leucine. The p.P1668L missense variant is predicted to be damaging by both SIFT and PolyPhen2. The proline residue at codon 1668 of SCN1A is conserved in all mammalian species. The nucleotide c.5003 in SCN1A is predicted conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
CADD	Uncertain	25
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.99	.;.;.;D;.;D;.;.;.
Eigen	Pathogenic	0.98
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D;D;D;.;.;.;D;D
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.9	.;.;.;H;.;H;.;.;.
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-8.7	.;.;.;D;.;D;.;D;D
REVEL	Pathogenic	0.89
Sift	Pathogenic	0.0	.;.;.;D;.;D;.;D;D
Sift4G	Pathogenic	0.0	.;.;.;D;.;D;.;D;D
Polyphen		1.0	.;.;.;.;D;.;D;D;.
Vest4		0.83, 0.87, 0.88, 0.93
MutPred		0.64		.;.;.;Gain of MoRF binding (P = 0.2353);.;Gain of MoRF binding (P = 0.2353);.;.;.;
MVP		0.99
MPC		1.8
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.79
gMVP		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-166848782;