rs139757692

Variant summary

Our verdict is Benign. The variant received -16 ACMG points: 1P and 17B. PP2BP4_StrongBP6_Very_StrongBS1BS2_Supporting

The NM_000083.3(CLCN1):​c.2207C>T​(p.Thr736Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000617 in 1,613,278 control chromosomes in the GnomAD database, including 13 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00079 ( 1 hom., cov: 31)
Exomes 𝑓: 0.00060 ( 12 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

18

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: 1.16

Publications

7 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: Benign. The variant received -16 ACMG points.

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.
BP4
Computational evidence support a benign effect (MetaRNN=0.0038505793).
BP6
Variant 7-143346174-C-T is Benign according to our data. Variant chr7-143346174-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 359120.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.000788 (120/152248) while in subpopulation EAS AF = 0.0216 (111/5146). AF 95% confidence interval is 0.0183. There are 1 homozygotes in GnomAd4. There are 61 alleles in the male GnomAd4 subpopulation. Median coverage is 31. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 12 AD,AR geneVariant has number of homozygotes lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CLCN1NM_000083.3 linkc.2207C>T p.Thr736Ile missense_variant Exon 18 of 23 ENST00000343257.7 NP_000074.3 P35523
CLCN1NR_046453.2 linkn.2162C>T non_coding_transcript_exon_variant Exon 17 of 22

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CLCN1ENST00000343257.7 linkc.2207C>T p.Thr736Ile missense_variant Exon 18 of 23 1 NM_000083.3 ENSP00000339867.2 P35523
CLCN1ENST00000432192.6 linkn.*1492C>T non_coding_transcript_exon_variant Exon 18 of 23 1 ENSP00000395949.2 H7C0N6
CLCN1ENST00000432192.6 linkn.*1492C>T 3_prime_UTR_variant Exon 18 of 23 1 ENSP00000395949.2 H7C0N6
CLCN1ENST00000650516.2 linkc.2207C>T p.Thr736Ile missense_variant Exon 18 of 23 ENSP00000498052.2 A0A3B3IU72

Frequencies

GnomAD3 genomes
AF:
0.000789
AC:
120
AN:
152130
Hom.:
1
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000393
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.0215
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.00158
AC:
398
AN:
251422
AF XY:
0.00146
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0210
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000652
GnomAD4 exome
AF:
0.000600
AC:
876
AN:
1461030
Hom.:
12
Cov.:
33
AF XY:
0.000592
AC XY:
430
AN XY:
726876
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33462
American (AMR)
AF:
0.000112
AC:
5
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.0210
AC:
833
AN:
39696
South Asian (SAS)
AF:
0.0000464
AC:
4
AN:
86226
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53410
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111242
Other (OTH)
AF:
0.000480
AC:
29
AN:
60372
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
50
100
150
200
250
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
20
40
60
80
100
<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:
0.000788
AC:
120
AN:
152248
Hom.:
1
Cov.:
31
AF XY:
0.000819
AC XY:
61
AN XY:
74444
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41544
American (AMR)
AF:
0.000392
AC:
6
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.0216
AC:
111
AN:
5146
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68026
Other (OTH)
AF:
0.000473
AC:
1
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
8
15
23
30
38
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00111
Hom.:
6
Bravo
AF:
0.00107
ExAC
AF:
0.00154
AC:
187
Asia WGS
AF:
0.00491
AC:
17
AN:
3478

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:3
Mar 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

CLCN1: BP4, BS1, BS2 -

Nov 19, 2021
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

See Variant Classification Assertion Criteria. -

Aug 15, 2018
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Batten-Turner congenital myopathy Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method: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 and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Congenital myotonia, autosomal recessive form;C2936781:Congenital myotonia, autosomal dominant form Benign:1
Dec 26, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.086
BayesDel_addAF
Benign
-0.52
T
BayesDel_noAF
Benign
-0.51
CADD
Benign
12
DANN
Benign
0.75
DEOGEN2
Benign
0.11
T
Eigen
Benign
-0.90
Eigen_PC
Benign
-0.93
FATHMM_MKL
Benign
0.078
N
LIST_S2
Benign
0.39
T
MetaRNN
Benign
0.0039
T
MetaSVM
Benign
-0.83
T
MutationAssessor
Benign
1.1
L
PhyloP100
1.2
PrimateAI
Benign
0.34
T
PROVEAN
Benign
-0.21
N
REVEL
Benign
0.12
Sift
Benign
0.23
T
Sift4G
Benign
0.21
T
Polyphen
0.0
B
Vest4
0.11
MVP
0.85
MPC
0.20
ClinPred
0.0082
T
GERP RS
2.4
Varity_R
0.046
gMVP
0.31
Mutation Taster
=96/4
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.12
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: rs139757692; hg19: chr7-143043267; API