17-63971844-G-C

Position:

• chr17-63971844-G-C

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BA1

The NM_000334.4(SCN4A):​c.489C>G​(p.Thr163=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00902 in 1,576,938 control chromosomes in the GnomAD database, including 144 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0090 (16 hom., cov: 30)
  • Exomes 𝑓: 0.0090 (128 hom.)
• Consequence: SCN4A NM_000334.4 synonymous
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:10
• Conservation: PhyloP100: -0.0970

Genes affected

SCN4A (HGNC:10591): (sodium voltage-gated channel alpha subunit 4) Voltage-gated sodium channels are transmembrane glycoprotein complexes composed of a large alpha subunit with 24 transmembrane domains and one or more regulatory beta subunits. They are responsible for the generation and propagation of action potentials in neurons and muscle. This gene encodes one member of the sodium channel alpha subunit gene family. It is expressed in skeletal muscle, and mutations in this gene have been linked to several myotonia and periodic paralysis disorders. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.55).
• BP6: Variant 17-63971844-G-C is Benign according to our data. Variant chr17-63971844-G-C is described in ClinVar as [Benign]. Clinvar id is 255858.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-63971844-G-C is described in Lovd as [Benign].
• BP7: Synonymous conserved (PhyloP=-0.097 with no splicing effect.
• BA1: GnomAdExome4 highest subpopulation (MID) allele frequency at 95% confidence interval = 0.0541 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN4A	NM_000334.4	c.489C>G	p.Thr163=	synonymous_variant	4/24	ENST00000435607.3	NP_000325.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN4A	ENST00000435607.3	c.489C>G	p.Thr163=	synonymous_variant	4/24	1	NM_000334.4	ENSP00000396320	P1

Frequencies

GnomAD3 genomes AF: 0.00906 AC: 1139 AN: 125658 Hom.: 16 Cov.: 30

Gnomad AFR AF: 0.00248

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00911

Gnomad ASJ AF: 0.0600

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.0186

Gnomad FIN AF: 0.00242

Gnomad MID AF: 0.0513

Gnomad NFE AF: 0.0108

Gnomad OTH AF: 0.0277

GnomAD3 exomes AF: 0.00995 AC: 2432 AN: 244512 Hom.: 26 AF XY: 0.0109 AC XY: 1449 AN XY: 132874

Gnomad AFR exome AF: 0.00126

Gnomad AMR exome AF: 0.00602

Gnomad ASJ exome AF: 0.0515

Gnomad EAS exome AF: 0.000114

Gnomad SAS exome AF: 0.0168

Gnomad FIN exome AF: 0.00257

Gnomad NFE exome AF: 0.00939

Gnomad OTH exome AF: 0.0162

GnomAD4 exome AF: 0.00902 AC: 13091 AN: 1451162 Hom.: 128 Cov.: 33 AF XY: 0.00961 AC XY: 6937 AN XY: 721686

Gnomad4 AFR exome AF: 0.00211

Gnomad4 AMR exome AF: 0.00602

Gnomad4 ASJ exome AF: 0.0508

Gnomad4 EAS exome AF: 0.0000512

Gnomad4 SAS exome AF: 0.0173

Gnomad4 FIN exome AF: 0.00230

Gnomad4 NFE exome AF: 0.00788

Gnomad4 OTH exome AF: 0.0132

GnomAD4 genome AF: 0.00905 AC: 1138 AN: 125776 Hom.: 16 Cov.: 30 AF XY: 0.00874 AC XY: 541 AN XY: 61896

Gnomad4 AFR AF: 0.00247

Gnomad4 AMR AF: 0.00910

Gnomad4 ASJ AF: 0.0600

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.0186

Gnomad4 FIN AF: 0.00242

Gnomad4 NFE AF: 0.0108

Gnomad4 OTH AF: 0.0273

Alfa AF: 0.0129 Hom.: 9

Bravo AF: 0.00762

Asia WGS AF: 0.00433 AC: 15 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:10

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:3

Benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -
Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Jul 16, 2020	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Feb 04, 2016	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Familial hyperkalemic periodic paralysis Benign:2

Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 31, 2024	- -
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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Hypokalemic periodic paralysis, type 2 Benign:1

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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Paramyotonia congenita of Von Eulenburg Benign:1

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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

not provided Benign:1

Benign, criteria provided, single submitter

not provided

Breakthrough Genomics, Breakthrough Genomics

-

- -

Potassium-aggravated myotonia Benign:1

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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Congenital myasthenic syndrome 16 Benign:1

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 benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.55
CADD	Benign	7.4
DANN	Benign	0.56

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: rs146590697; hg19: chr17-62049204;