rs143146088

Positions:

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_000083.3(CLCN1):c.2464G>A(p.Asp822Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000248 in 1,614,040 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.19

Variant links:

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]

CLCN1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.899

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLCN1	NM_000083.3 linkuse as main transcript	c.2464G>A	p.Asp822Asn	missense_variant	21/23	ENST00000343257.7	NP_000074.3
CLCN1	NR_046453.2 linkuse as main transcript	n.2419G>A		non_coding_transcript_exon_variant	20/22

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris
CLCN1	ENST00000343257.7 linkuse as main transcript	c.2464G>A	p.Asp822Asn	missense_variant	21/23	1	NM_000083.3	ENSP00000339867	P4
CLCN1	ENST00000432192.6 linkuse as main transcript	c.*1749G>A		3_prime_UTR_variant, NMD_transcript_variant	21/23	1		ENSP00000395949
CLCN1	ENST00000650516.2 linkuse as main transcript	c.2464G>A	p.Asp822Asn	missense_variant	21/23			ENSP00000498052	A2

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152172

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.0000239

AC:

AN:

1461868

Hom.:

Cov.:

AF XY:

0.0000261

AC XY:

AN XY:

727238

show subpopulations

Gnomad4 AFR exome

AF:

0.0000597

Gnomad4 AMR exome

AF:

0.00

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:

0.0000297

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152172

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74332

show subpopulations

Gnomad4 AFR

AF:

0.0000483

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000658

Hom.:

Bravo

AF:

0.0000264

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

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

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 16, 2022

This sequence change replaces aspartic acid, which is acidic and polar, with asparagine, which is neutral and polar, at codon 822 of the CLCN1 protein (p.Asp822Asn). This variant is present in population databases (rs143146088, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with CLCN1-related conditions. 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on CLCN1 protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.73

BayesDel_addAF

Uncertain

0.068

BayesDel_noAF

Benign

-0.14

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.52

Eigen

Pathogenic

0.80

Eigen_PC

Pathogenic

0.74

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.90

M_CAP

Uncertain

0.19

MetaRNN

Pathogenic

0.90

MetaSVM

Uncertain

0.73

MutationAssessor

Benign

1.2

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.68

PROVEAN

Uncertain

-3.9

REVEL

Uncertain

0.62

Sift

Uncertain

0.023

Sift4G

Uncertain

0.0030

Polyphen

1.0

Vest4

0.94

MVP

0.97

MPC

0.73

ClinPred

0.99

GERP RS

4.5

Varity_R

0.67

gMVP

0.79

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.070

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over