rs149578972

chr7-143330818-G-A

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_Strong BP6_Very_Strong BP7

The NM_000083.3(CLCN1):c.900G>A(p.Arg300=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000326 in 1,614,056 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. R300?) has been classified as Pathogenic.

• Frequency:
  • Genomes: 𝑓 0.00022 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00034 (1 hom.)
• Consequence: CLCN1 NM_000083.3 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5
• Conservation: PhyloP100: 0.180

Genes affected

CLCN1 (HGNC:2019): (chloride voltage-gated channel 1) The CLCN family of voltage-dependent chloride channel genes comprises nine members (CLCN1-7, Ka and Kb) which demonstrate quite diverse functional characteristics while sharing significant sequence homology. The protein encoded by this gene regulates the electric excitability of the skeletal muscle membrane. Mutations in this gene cause two forms of inherited human muscle disorders: recessive generalized myotonia congenita (Becker) and dominant myotonia (Thomsen). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Mar 2012]

ACMG classification

Verdict is Benign. Variant got -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.55).
• BP6: Variant 7-143330818-G-A is Benign according to our data. Variant chr7-143330818-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 390519.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.18 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CLCN1	NM_000083.3	c.900G>A	p.Arg300=	synonymous_variant	8/23	ENST00000343257.7
CLCN1	NR_046453.2	n.1005G>A		non_coding_transcript_exon_variant	8/22

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CLCN1	ENST00000343257.7	c.900G>A	p.Arg300=	synonymous_variant	8/23	1	NM_000083.3	P4

Frequencies

GnomAD3 genomes AF: 0.000223 AC: 34 AN: 152184 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000131

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000426

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000127 AC: 32 AN: 251396 Hom.: 0 AF XY: 0.000140 AC XY: 19 AN XY: 135868

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000273

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000337 AC: 492 AN: 1461872 Hom.: 1 Cov.: 32 AF XY: 0.000337 AC XY: 245 AN XY: 727236

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.000413

Gnomad4 OTH exome AF: 0.000530

GnomAD4 genome AF: 0.000223 AC: 34 AN: 152184 Hom.: 0 Cov.: 32 AF XY: 0.000148 AC XY: 11 AN XY: 74354

Gnomad4 AFR AF: 0.0000724

Gnomad4 AMR AF: 0.000131

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000426

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000376 Hom.: 0

Bravo AF: 0.000238

EpiCase AF: 0.000654

EpiControl AF: 0.000178

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:2

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Nov 14, 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. -
Likely benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Apr 16, 2021	- -

Batten-Turner congenital myopathy Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jul 07, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Congenital myotonia, autosomal recessive form;C2936781:Congenital myotonia, autosomal dominant form Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jan 30, 2024

- -

CLCN1-related disorder Benign:1

Likely benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Apr 12, 2019

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.55
Cadd	Benign	5.5
Dann	Benign	0.65

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs149578972; hg19: chr7-143027911;