rs767209392

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM1PP2

The NM_000083.3(CLCN1):​c.2578G>A​(p.Val860Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000297 in 1,613,810 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. V860V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

1
8
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 6.28

Publications

4 publications found
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 Gene-Disease associations (from GenCC):
  • myotonia congenita, autosomal dominant
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • myotonia congenita, autosomal recessive
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • Thomsen and Becker disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a domain CBS 2 (size 55) in uniprot entity CLCN1_HUMAN there are 4 pathogenic changes around while only 0 benign (100%) in NM_000083.3
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 106 curated pathogenic missense variants (we use a threshold of 10). The gene has 18 curated benign missense variants. Gene score misZ: 0.21191 (below the threshold of 3.09). Trascript score misZ: 0.95247 (below the threshold of 3.09). GenCC associations: The gene is linked to myotonia congenita, autosomal dominant, myotonia congenita, autosomal recessive, Thomsen and Becker disease.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CLCN1NM_000083.3 linkc.2578G>A p.Val860Ile missense_variant Exon 22 of 23 ENST00000343257.7 NP_000074.3
CLCN1NR_046453.2 linkn.2533G>A non_coding_transcript_exon_variant Exon 21 of 22

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CLCN1ENST00000343257.7 linkc.2578G>A p.Val860Ile missense_variant Exon 22 of 23 1 NM_000083.3 ENSP00000339867.2
CLCN1ENST00000432192.6 linkn.*1863G>A non_coding_transcript_exon_variant Exon 22 of 23 1 ENSP00000395949.2
CLCN1ENST00000432192.6 linkn.*1863G>A 3_prime_UTR_variant Exon 22 of 23 1 ENSP00000395949.2
CLCN1ENST00000650516.2 linkc.2578G>A p.Val860Ile missense_variant Exon 22 of 23 ENSP00000498052.2

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152168
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251402
AF XY:
0.0000147
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000294
AC:
43
AN:
1461642
Hom.:
0
Cov.:
32
AF XY:
0.0000316
AC XY:
23
AN XY:
727140
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.0000812
AC:
7
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000279
AC:
31
AN:
1111796
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
3
6
8
11
14
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000329
AC:
5
AN:
152168
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74344
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41436
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000302
ExAC
AF:
0.00000824
AC:
1
Asia WGS
AF:
0.000577
AC:
2
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Oct 07, 2021
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 27, 2021
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Congenital myotonia, autosomal recessive form;C2936781:Congenital myotonia, autosomal dominant form Uncertain:1
Apr 06, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 860 of the CLCN1 protein (p.Val860Ile). This variant is present in population databases (rs767209392, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with CLCN1-related conditions. ClinVar contains an entry for this variant (Variation ID: 202176). 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. -

Congenital myotonia, autosomal dominant form Uncertain:1
May 13, 2016
Mendelics
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
BayesDel_addAF
Benign
-0.054
T
BayesDel_noAF
Benign
-0.13
CADD
Pathogenic
30
DANN
Uncertain
1.0
DEOGEN2
Benign
0.14
T
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.57
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.92
D
M_CAP
Benign
0.056
D
MetaRNN
Uncertain
0.49
T
MetaSVM
Uncertain
0.29
D
MutationAssessor
Benign
1.4
L
PhyloP100
6.3
PrimateAI
Uncertain
0.54
T
PROVEAN
Benign
-0.45
N
REVEL
Uncertain
0.41
Sift
Benign
0.21
T
Sift4G
Benign
0.16
T
Polyphen
1.0
D
Vest4
0.19
MutPred
0.44
Loss of catalytic residue at V860 (P = 0.0534);
MVP
0.85
MPC
0.40
ClinPred
0.68
D
GERP RS
4.2
Varity_R
0.10
gMVP
0.49
Mutation Taster
=58/42
polymorphism

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

Other links and lift over

dbSNP: rs767209392; hg19: chr7-143047730; API