NM_000083.3:c.2339G>A

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 1P and 7B. PP2BP4_StrongBP6_ModerateBS2_Supporting

The NM_000083.3(CLCN1):​c.2339G>A​(p.Arg780His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000133 in 1,613,684 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R780L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00014 ( 2 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

18

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 0.188

Publications

0 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: Likely_benign. The variant received -6 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=0.007011324).
BP6
Variant 7-143346633-G-A is Benign according to our data. Variant chr7-143346633-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 531742.Status of the report is criteria_provided_single_submitter, 1 stars.
BS2
High Homozygotes in GnomAdExome4 at 2 AD,AR geneVariant has number of homozygotes lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000083.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CLCN1
NM_000083.3
MANE Select
c.2339G>Ap.Arg780His
missense
Exon 19 of 23NP_000074.3
CLCN1
NR_046453.2
n.2294G>A
non_coding_transcript_exon
Exon 18 of 22

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CLCN1
ENST00000343257.7
TSL:1 MANE Select
c.2339G>Ap.Arg780His
missense
Exon 19 of 23ENSP00000339867.2
CLCN1
ENST00000432192.6
TSL:1
n.*1624G>A
non_coding_transcript_exon
Exon 19 of 23ENSP00000395949.2
CLCN1
ENST00000432192.6
TSL:1
n.*1624G>A
3_prime_UTR
Exon 19 of 23ENSP00000395949.2

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152118
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00269
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000239
AC:
60
AN:
250794
AF XY:
0.000302
show subpopulations
Gnomad AFR exome
AF:
0.00
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:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000137
AC:
200
AN:
1461448
Hom.:
2
Cov.:
32
AF XY:
0.000201
AC XY:
146
AN XY:
727054
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00216
AC:
186
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53120
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111890
Other (OTH)
AF:
0.000132
AC:
8
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.486
Heterozygous variant carriers
0
13
26
39
52
65
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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:
0.0000920
AC:
14
AN:
152236
Hom.:
0
Cov.:
32
AF XY:
0.000161
AC XY:
12
AN XY:
74438
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41544
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5162
South Asian (SAS)
AF:
0.00269
AC:
13
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68014
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000868
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.000214
AC:
26
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

ClinVar submissions as Germline

Significance:Likely benign
Revision:criteria provided, single submitter
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
1
Congenital myotonia, autosomal recessive form;C2936781:Congenital myotonia, autosomal dominant form (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.063
BayesDel_addAF
Benign
-0.44
T
BayesDel_noAF
Benign
-0.42
CADD
Benign
13
DANN
Benign
0.79
DEOGEN2
Benign
0.14
T
Eigen
Benign
-1.0
Eigen_PC
Benign
-1.1
FATHMM_MKL
Benign
0.035
N
LIST_S2
Benign
0.69
T
M_CAP
Benign
0.016
T
MetaRNN
Benign
0.0070
T
MetaSVM
Benign
-0.79
T
MutationAssessor
Benign
0.81
L
PhyloP100
0.19
PrimateAI
Benign
0.27
T
PROVEAN
Benign
-0.42
N
REVEL
Benign
0.10
Sift
Benign
0.29
T
Sift4G
Benign
0.16
T
Polyphen
0.0070
B
Vest4
0.19
MutPred
0.53
Loss of MoRF binding (P = 0.011)
MVP
0.76
MPC
0.23
ClinPred
0.020
T
GERP RS
-0.95
Varity_R
0.023
gMVP
0.21
Mutation Taster
=95/5
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs529481237; hg19: chr7-143043726; COSMIC: COSV58368704; API