2-165989381-A-T

Variant names:

• chr2-165989381-A-T
• rs150155252
• NM_001165963.4:c.*1864T>A

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_Strong BP6 BS1 BS2

The NM_001165963.4(SCN1A):​c.*1864T>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00327 in 152,634 control chromosomes in the GnomAD database, including 2 homozygotes. 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: 𝑓 0.0033 (2 hom., cov: 32)
  • Exomes 𝑓: 0.0024 (0 hom.)
• Consequence: SCN1A NM_001165963.4 3_prime_UTR
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:3
• Conservation: PhyloP100: 0.0190

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 Benign. Variant got -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.63).
• BP6: Variant 2-165989381-A-T is Benign according to our data. Variant chr2-165989381-A-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 331860.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=3, Uncertain_significance=1}.
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00327 (498/152216) while in subpopulation NFE AF= 0.00507 (345/68012). AF 95% confidence interval is 0.00463. There are 2 homozygotes in gnomad4. There are 224 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 498 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN1A	NM_001165963.4	c.*1864T>A		3_prime_UTR_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	c.*1864T>A		3_prime_UTR_variant	Exon 29 of 29		NM_001165963.4	ENSP00000501589.1
SCN1A	ENST00000303395	c.*1864T>A		3_prime_UTR_variant	Exon 28 of 28	5		ENSP00000303540.4
SCN1A	ENST00000375405	c.*1864T>A		3_prime_UTR_variant	Exon 26 of 26	5		ENSP00000364554.3

Frequencies

GnomAD3 genomes AF: 0.00327 AC: 498 AN: 152098 Hom.: 2 Cov.: 32

Gnomad AFR AF: 0.00113

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00170

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00698

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00507

Gnomad OTH AF: 0.00287

GnomAD4 exome AF: 0.00239 AC: 1 AN: 418 Hom.: 0 Cov.: 0 AF XY: 0.00394 AC XY: 1 AN XY: 254

Gnomad4 FIN exome AF: 0.00243

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00327 AC: 498 AN: 152216 Hom.: 2 Cov.: 32 AF XY: 0.00301 AC XY: 224 AN XY: 74420

Gnomad4 AFR AF: 0.00113

Gnomad4 AMR AF: 0.00170

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00698

Gnomad4 NFE AF: 0.00507

Gnomad4 OTH AF: 0.00284

Alfa AF: 0.00392 Hom.: 0

Bravo AF: 0.00279

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Generalized epilepsy with febrile seizures plus, type 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Migraine, familial hemiplegic, 3 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Nov 01, 2023

SCN1A: BS1 -

Epilepsy Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.63
CADD	Benign	0.69
DANN	Benign	0.65

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

LitVar

Other links and lift over

dbSNP: rs150155252; hg19: chr2-166845891;