7-143324465-G-A

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1PP2PP3PP5

The NM_000083.3(CLCN1):​c.826G>A​(p.Gly276Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000217 in 1,613,790 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G276C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

5
9
4

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:2

Conservation

PhyloP100: 9.95

Publications

3 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: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • 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 5 ACMG points.

PM1
In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 uncertain 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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.839
PP5
Variant 7-143324465-G-A is Pathogenic according to our data. Variant chr7-143324465-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 447072.

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

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CLCN1
NM_000083.3
MANE Select
c.826G>Ap.Gly276Ser
missense
Exon 7 of 23NP_000074.3
CLCN1
NR_046453.2
n.931G>A
non_coding_transcript_exon
Exon 7 of 22

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CLCN1
ENST00000343257.7
TSL:1 MANE Select
c.826G>Ap.Gly276Ser
missense
Exon 7 of 23ENSP00000339867.2
CLCN1
ENST00000432192.6
TSL:1
n.*111G>A
non_coding_transcript_exon
Exon 7 of 23ENSP00000395949.2
CLCN1
ENST00000455478.6
TSL:1
n.*111G>A
non_coding_transcript_exon
Exon 6 of 7ENSP00000400027.2

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152062
Hom.:
0
Cov.:
33
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
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
251492
AF XY:
0.0000294
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000578
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:
0.000163
GnomAD4 exome
AF:
0.0000205
AC:
30
AN:
1461728
Hom.:
0
Cov.:
31
AF XY:
0.0000261
AC XY:
19
AN XY:
727156
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.0000894
AC:
4
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.000176
AC:
1
AN:
5670
European-Non Finnish (NFE)
AF:
0.0000216
AC:
24
AN:
1111972
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.460
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000329
AC:
5
AN:
152062
Hom.:
0
Cov.:
33
AF XY:
0.0000404
AC XY:
3
AN XY:
74284
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41380
American (AMR)
AF:
0.00
AC:
0
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5164
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000986
Hom.:
0
Bravo
AF:
0.0000340
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

ClinVar submissions as Germline
Significance:Conflicting classifications of pathogenicity
Revision:criteria provided, conflicting classifications
View on ClinVar
Pathogenic
VUS
Benign
Condition
2
-
-
Congenital myotonia, autosomal recessive form;C2936781:Congenital myotonia, autosomal dominant form (2)
1
1
-
not provided (2)
-
1
-
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.32
BayesDel_addAF
Uncertain
0.14
D
BayesDel_noAF
Pathogenic
0.14
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.76
D
Eigen
Uncertain
0.31
Eigen_PC
Uncertain
0.43
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.97
D
M_CAP
Uncertain
0.26
D
MetaRNN
Pathogenic
0.84
D
MetaSVM
Uncertain
0.060
D
MutationAssessor
Benign
-0.82
N
PhyloP100
10
PrimateAI
Pathogenic
0.90
D
PROVEAN
Uncertain
-3.4
D
REVEL
Pathogenic
0.67
Sift
Benign
0.22
T
Sift4G
Benign
0.35
T
Polyphen
0.96
D
Vest4
0.84
MutPred
0.63
Gain of glycosylation at G276 (P = 0.0342)
MVP
0.95
MPC
0.58
ClinPred
0.69
D
GERP RS
4.8
Varity_R
0.88
gMVP
0.85
Mutation Taster
=7/93
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.060
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: rs765181341; hg19: chr7-143021558; API