Submissions for variant NM_000334.4(SCN4A):c.4324G>A (p.Val1442Met)

gnomAD frequency: 0.00001  dbSNP: rs774452124

Total submissions: 8

Submitter	RCV	SCV	Clinical significance	Condition	Last evaluated	Review status	Method	Comment
Illumina Laboratory Services, Illumina	RCV000344057	SCV000405051	uncertain significance	Congenital myasthenic syndrome 16	2018-01-13	criteria provided, single submitter	clinical testing	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.
Illumina Laboratory Services, Illumina	RCV000392378	SCV000405052	uncertain significance	Hyperkalemic periodic paralysis	2018-01-13	criteria provided, single submitter	clinical testing	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.
Illumina Laboratory Services, Illumina	RCV000313533	SCV000405053	uncertain significance	Potassium-aggravated myotonia	2018-01-13	criteria provided, single submitter	clinical testing	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.
Illumina Laboratory Services, Illumina	RCV000368322	SCV000405054	uncertain significance	Paramyotonia congenita of Von Eulenburg	2018-01-13	criteria provided, single submitter	clinical testing	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.
Illumina Laboratory Services, Illumina	RCV000405474	SCV000405055	uncertain significance	Hypokalemic periodic paralysis, type 2	2018-01-13	criteria provided, single submitter	clinical testing	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.
Fulgent Genetics, Fulgent Genetics	RCV002502255	SCV002814212	uncertain significance	Hypokalemic periodic paralysis, type 1; Potassium-aggravated myotonia; Paramyotonia congenita of Von Eulenburg; Hypokalemic periodic paralysis, type 2; Hyperkalemic periodic paralysis; Congenital myasthenic syndrome 16	2021-08-24	criteria provided, single submitter	clinical testing
Invitae	RCV000392378	SCV003027690	uncertain significance	Hyperkalemic periodic paralysis	2023-12-12	criteria provided, single submitter	clinical testing	This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 1442 of the SCN4A protein (p.Val1442Met). This variant is present in population databases (rs774452124, gnomAD 0.004%). This missense change has been observed in individual(s) with sudden infant death syndrome (PMID: 29605429). ClinVar contains an entry for this variant (Variation ID: 324517). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt SCN4A protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects SCN4A function (PMID: 29605429). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.
Revvity Omics, Revvity	RCV003137925	SCV003821268	uncertain significance	not provided	2021-12-29	criteria provided, single submitter	clinical testing