rs777685454

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1PM5PP2PP3_StrongPP5

The NM_000083.3(CLCN1):​c.1606G>A​(p.Val536Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,613,744 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. V536A) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

12
4
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:1

Conservation

PhyloP100: 9.99

Publications

9 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: Pathogenic. The variant received 10 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_000083.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chr7-143341953-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2926032.
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, 0.974
PP5
Variant 7-143341952-G-A is Pathogenic according to our data. Variant chr7-143341952-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 447054.

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.1606G>Ap.Val536Ile
missense
Exon 15 of 23NP_000074.3P35523
CLCN1
NR_046453.2
n.1561G>A
non_coding_transcript_exon
Exon 14 of 22

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CLCN1
ENST00000343257.7
TSL:1 MANE Select
c.1606G>Ap.Val536Ile
missense
Exon 15 of 23ENSP00000339867.2P35523
CLCN1
ENST00000432192.6
TSL:1
n.*891G>A
non_coding_transcript_exon
Exon 15 of 23ENSP00000395949.2H7C0N6
CLCN1
ENST00000432192.6
TSL:1
n.*891G>A
3_prime_UTR
Exon 15 of 23ENSP00000395949.2H7C0N6

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152198
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:
0.00
Gnomad FIN
AF:
0.000188
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
251390
AF XY:
0.0000294
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000924
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000192
AC:
28
AN:
1461546
Hom.:
0
Cov.:
33
AF XY:
0.0000151
AC XY:
11
AN XY:
727084
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33472
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86238
European-Finnish (FIN)
AF:
0.0000562
AC:
3
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5512
European-Non Finnish (NFE)
AF:
0.0000180
AC:
20
AN:
1111992
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60354
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
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:
0.0000263
AC:
4
AN:
152198
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74358
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.000188
AC:
2
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.538
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000272
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

ClinVar submissions
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
-
-
Congenital myotonia, autosomal recessive form (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
BayesDel_addAF
Pathogenic
0.22
D
BayesDel_noAF
Pathogenic
0.27
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.55
D
Eigen
Pathogenic
0.99
Eigen_PC
Pathogenic
0.97
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D
M_CAP
Pathogenic
0.56
D
MetaRNN
Pathogenic
0.97
D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.0
M
PhyloP100
10
PrimateAI
Uncertain
0.62
T
PROVEAN
Benign
-0.82
N
REVEL
Pathogenic
0.67
Sift
Uncertain
0.0030
D
Sift4G
Uncertain
0.0060
D
Polyphen
1.0
D
Vest4
0.90
MutPred
0.85
Loss of sheet (P = 0.0817)
MVP
0.97
MPC
0.66
ClinPred
0.69
D
GERP RS
5.9
Varity_R
0.68
gMVP
0.81
Mutation Taster
=17/83
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.14
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: rs777685454; hg19: chr7-143039045; COSMIC: COSV58370113; API