VCV000939897.26 - ClinVar

NM_000083.3(CLCN1):c.1190T>A (p.Val397Asp)

Germline

Classification

criteria provided, multiple submitters, no conflicts. Learn more about how ClinVar calculates review status.

Uncertain significance
Uncertain significance (2)

2 out of 2 submissions contributed to this classification

The aggregate germline classification for this variant, typically for a monogenic or Mendelian disorder as in the ACMG/AMP guidelines, or for response to a drug. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the aggregate classification.

Somatic

No data submitted for somatic clinical impact

Somatic

No data submitted for oncogenicity

Variant Details

Identifiers

NM_000083.3(CLCN1):c.1190T>A (p.Val397Asp)

Variation ID: 939897 Accession: VCV000939897.26

Type and length

single nucleotide variant, 1 bp

Location

Cytogenetic: 7q34 7: 143332442 (GRCh38) [ NCBI UCSC ] 7: 143029535 (GRCh37) [ NCBI UCSC ]

Timeline in ClinVar

	First in ClinVar Help The date this variant first appeared in ClinVar with each type of classification.	Last submission Help The date of the most recent submission for each type of classification for this variant.	Last evaluated Help The most recent date that a submitter evaluated this variant for each type of classification.
Germline	Jul 16, 2020	Feb 23, 2026	May 22, 2023

HGVS

Nucleotide	Protein	Molecular consequence
NM_000083.3:c.1190T>A MANE Select Help Transcripts from the Matched Annotation from the NCBI and EMBL-EBI (MANE) collaboration.	NP_000074.3:p.Val397Asp	missense
NR_046453.2:n.1295T>A		non-coding transcript variant
NC_000007.14:g.143332442T>A
NC_000007.13:g.143029535T>A
NG_009815.2:g.21317T>A

... more HGVS ... less HGVS

Protein change

V397D

Other names

Canonical SPDI

NC_000007.14:143332441:T:A

Global minor allele frequency (GMAF) Help The global minor allele frequency calculated by the 1000 Genomes Project. The minor allele at this location is indicated in parentheses and may be different from the allele represented by this VCV record.

Allele frequency Help The frequency of the allele represented by this VCV record.

Links

ClinGen: CA369643229 dbSNP: rs368958317 VarSome

Genes

Gene	OMIM	ClinGen Gene Dosage Sensitivity Curation		Variation Viewer Help Links to Variation Viewer, a genome browser to view variation data from NCBI databases.	Related variants
Gene	OMIM	HI score Help The haploinsufficiency score for the gene, curated by ClinGen’s Dosage Sensitivity Curation task team.	TS score Help The triplosensitivity score for the gene, curated by ClinGen’s Dosage Sensitivity Curation task team.		Within gene Help The number of variants in ClinVar that are contained within this gene, with a link to view the list of variants.	All Help The number of variants in ClinVar for this gene, including smaller variants within the gene and larger CNVs that overlap or fully contain the gene.
CLCN1		-	-	GRCh38 GRCh37	1634	1814

Conditions - Germline

Condition Help The condition for this variant-condition (RCV) record in ClinVar.	Classification Help The aggregate germline classification for this variant-condition (RCV) record in ClinVar. The number of submissions that contribute to this aggregate classification is shown in parentheses. (# of submissions)	Review status Help The aggregate review status for this variant-condition (RCV) record in ClinVar. This value is calculated by NCBI based on data from submitters. Read our rules for calculating the review status.	Last evaluated Help The most recent date that a submitter evaluated this variant for the condition.	Variation/condition record Help The RCV accession number, with most recent version number, for the variant-condition record, with a link to the RCV web page.
Congenital myotonia, autosomal dominant form Congenital myotonia, autosomal recessive form	Uncertain significance (1)	criteria provided, single submitter	May 22, 2023	RCV001209375.10
Congenital myotonia, autosomal recessive form	Uncertain significance (1)	criteria provided, single submitter	Feb 1, 2013	RCV002466266.1

Submissions - Germline

Classification Help The submitted germline classification for each SCV record. (Last evaluated)	Review status Help Stars represent the review status, or the level of review supporting the submitted (SCV) record. This value is calculated by NCBI based on data from the submitter. Read our rules for calculating the review status. This column also includes a link to the submitter’s assertion criteria if provided, and the collection method. (Assertion criteria)	Condition Help The condition for the classification, provided by the submitter for this submitted (SCV) record. This column also includes the affected status and allele origin of individuals observed with this variant.	Submitter Help The submitting organization for this submitted (SCV) record. This column also includes the SCV accession and version number, the date this SCV first appeared in ClinVar, and the date that this SCV was last updated in ClinVar.	Expand all rows Collapse all rows Help This column includes more information supporting the classification, including citations, the comment on classification, and detailed evidence provided as observations of the variant by the submitter.
Uncertain significance (Feb 01, 2013) C Contributing to aggregate classification	criteria provided, single submitter (ACMG Guidelines, 2015)	Congenital myotonia, autosomal recessive form	Arcensus Accession: SCV002564621.1 First in ClinVar: Dec 17, 2022 Last updated: Dec 17, 2022	Observation: 1 Collection method: clinical testing Allele origin: germline Affected status: yes Observation 1 Collection method: clinical testing Allele origin: germline Affected status: yes

Uncertain significance (May 22, 2023) C Contributing to aggregate classification	criteria provided, single submitter (Invitae Variant Classification Sherloc (09022015))	Congenital myotonia, autosomal recessive form Congenital myotonia, autosomal dominant form Explanation for multiple conditions: Uncertain. The variant was classified for several related diseases, possibly a spectrum of disease; the variant may be associated with one or more the diseases.	Labcorp Genetics (formerly Invitae), Labcorp Accession: SCV001380807.7 First in ClinVar: Jul 16, 2020 Last updated: Feb 23, 2026	Publications: PubMed (1) PubMed: 34529042 Comment: show 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. Experimental studies have shown that this missense change affects CLCN1 function (PMID: 34529042). 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 CLCN1 protein function. ClinVar contains an entry for this variant (Variation ID: 939897). This missense change has been observed in individual(s) with clinical features of CLCN1-related conditions (PMID: 34529042). This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change replaces valine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 397 of the CLCN1 protein (p.Val397Asp). (less) Observation: 1 Collection method: clinical testing Allele origin: germline Affected status: unknown Observation 1 Collection method: clinical testing Allele origin: germline Affected status: unknown

Comment:

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. Experimental studies have shown that this missense change affects CLCN1 function (PMID: 34529042). 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 CLCN1 protein function. ClinVar contains an entry for this variant (Variation ID: 939897). This missense change has been observed in individual(s) with clinical features of CLCN1-related conditions (PMID: 34529042). This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change replaces valine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 397 of the CLCN1 protein (p.Val397Asp).

Citations for germline classification of this variant

Title	Author	Journal	Year	Link
Translating genetic and functional data into clinical practice: a series of 223 families with myotonia.	Suetterlin K	Brain : a journal of neurology	2022	PMID: 34529042

Text-mined citations for rs368958317 ...

These citations are identified by LitVar using the rs number, so they may include citations for more than one variant at this location. Please review the LitVar results carefully for your variant of interest.

Record last updated Feb 24, 2026