rs1553463718

Variant names:

• chr2-165389357-C-T
• rs1553463718
• NM_001040142.2:c.5551C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP2 PP3_Moderate PP5

The NM_001040142.2(SCN2A):​c.5551C>T​(p.Arg1851Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SCN2A NM_001040142.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:2
• Conservation: PhyloP100: 0.757
• Publications: 0 publications found

Genes affected

SCN2A (HGNC:10588): (sodium voltage-gated channel alpha subunit 2) Voltage-gated sodium channels are transmembrane glycoprotein complexes composed of a large alpha subunit with four repeat domains, each of which is composed of six membrane-spanning segments, and one or more regulatory beta subunits. Voltage-gated sodium channels function in the generation and propagation of action potentials in neurons and muscle. This gene encodes one member of the sodium channel alpha subunit gene family. Allelic variants of this gene are associated with seizure disorders and autism spectrum disorder. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2016]

SCN2A Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Illumina
• developmental and epileptic encephalopathy, 11

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• intellectual disability

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• episodic ataxia, type 9

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• seizures, benign familial infantile, 3

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• benign familial infantile epilepsy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• benign familial neonatal-infantile seizures

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Dravet syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• genetic developmental and epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• malignant migrating partial seizures of infancy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_001040142.2
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the SCN2A gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 362 curated pathogenic missense variants (we use a threshold of 10). The gene has 36 curated benign missense variants. Trascript score misZ: 8.7114 (above the threshold of 3.09). GenCC associations: The gene is linked to genetic developmental and epileptic encephalopathy, episodic ataxia, type 9, seizures, benign familial infantile, 3, complex neurodevelopmental disorder, benign familial neonatal-infantile seizures, Dravet syndrome, infantile spasms, developmental and epileptic encephalopathy, 11, intellectual disability, benign familial infantile epilepsy, malignant migrating partial seizures of infancy.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.897
• PP5: Variant 2-165389357-C-T is Pathogenic according to our data. Variant chr2-165389357-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 495262.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN2A	NM_001040142.2	c.5551C>T	p.Arg1851Trp	missense_variant	Exon 27 of 27	ENST00000375437.7	NP_001035232.1
SCN2A	NM_001371246.1	c.5551C>T	p.Arg1851Trp	missense_variant	Exon 27 of 27	ENST00000631182.3	NP_001358175.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN2A	ENST00000375437.7	c.5551C>T	p.Arg1851Trp	missense_variant	Exon 27 of 27	5	NM_001040142.2	ENSP00000364586.2
SCN2A	ENST00000631182.3	c.5551C>T	p.Arg1851Trp	missense_variant	Exon 27 of 27	5	NM_001371246.1	ENSP00000486885.1
SCN2A	ENST00000283256.10	c.5551C>T	p.Arg1851Trp	missense_variant	Exon 27 of 27	1		ENSP00000283256.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Seizures, benign familial infantile, 3 Pathogenic:1

Jan 01, 2018

NeuroMeGen, Hospital Clinico Santiago de Compostela

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Inborn genetic diseases Uncertain:1

Dec 18, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.5551C>T (p.R1851W) alteration is located in exon 27 (coding exon 26) of the SCN2A gene. This alteration results from a C to T substitution at nucleotide position 5551, causing the arginine (R) at amino acid position 1851 to be replaced by a tryptophan (W). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). This variant was reported in an individual with features consistent with SCN2A-related disorders (Fernández-Marmiesse, 2019). This amino acid position is highly conserved in available vertebrate species. This alteration is predicted to be deleterious by in silico analysis. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Complex neurodevelopmental disorder Uncertain:1

Jan 29, 2019

GenomeConnect - Simons Searchlight

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: provider interpretation

Submission from Simons Searchlight facilitated by GenomeConnect. Variant interpreted by the Simons Searchlight team most recently on 2019-01-29 and interpreted as Variant of Uncertain significance. Variant was initially reported on 2017-09-25. The reporting laboratory might also submit to ClinVar. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.87	D;.;T;.;D;D;.
Eigen	Uncertain	0.59
Eigen_PC	Uncertain	0.49
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Pathogenic	0.99	D;.;D;.;.;.;D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.90	D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.6	H;H;.;H;H;H;H
PhyloP100		0.76
PrimateAI	Pathogenic	0.92	D
PROVEAN	Pathogenic	-7.3	D;.;.;.;.;D;D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	D;.;.;.;.;D;D
Sift4G	Pathogenic	0.0	D;.;.;D;.;D;D
Polyphen		1.0	D;D;.;D;D;D;D
Vest4		0.66
MutPred		0.56		Gain of glycosylation at S1848 (P = 0.1051);Gain of glycosylation at S1848 (P = 0.1051);.;Gain of glycosylation at S1848 (P = 0.1051);Gain of glycosylation at S1848 (P = 0.1051);Gain of glycosylation at S1848 (P = 0.1051);Gain of glycosylation at S1848 (P = 0.1051);
MVP		0.98
ClinPred		1.0	D
GERP RS		3.7
Varity_R		0.91
gMVP		0.98
Mutation Taster		=17/83	disease causing (ClinVar)

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: rs1553463718; hg19: chr2-166245867; COSMIC: COSV51854555;