rs754934082

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM1PP2BP4

The NM_000083.3(CLCN1):​c.750G>A​(p.Met250Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000031 in 1,613,544 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M250T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

8
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 5.73

Publications

1 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 2 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 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.
BP4
Computational evidence support a benign effect (MetaRNN=0.365346).

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.750G>Ap.Met250Ile
missense
Exon 6 of 23NP_000074.3
CLCN1
NR_046453.2
n.852G>A
non_coding_transcript_exon
Exon 6 of 22

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CLCN1
ENST00000343257.7
TSL:1 MANE Select
c.750G>Ap.Met250Ile
missense
Exon 6 of 23ENSP00000339867.2
CLCN1
ENST00000455478.6
TSL:1
n.204G>A
non_coding_transcript_exon
Exon 3 of 7ENSP00000400027.2
CLCN1
ENST00000432192.6
TSL:1
n.463-211G>A
intron
N/AENSP00000395949.2

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
152068
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000318
AC:
8
AN:
251448
AF XY:
0.0000221
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:
0.0000462
Gnomad NFE exome
AF:
0.0000616
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000328
AC:
48
AN:
1461476
Hom.:
0
Cov.:
30
AF XY:
0.0000426
AC XY:
31
AN XY:
727046
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33464
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.0000374
AC:
2
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000405
AC:
45
AN:
1111656
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60376
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
3
7
10
14
17
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:
0.0000132
AC:
2
AN:
152068
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74254
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41412
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10588
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000502
Hom.:
0
Bravo
AF:
0.0000189
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

ClinVar submissions as Germline

Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
-
not provided (2)
-
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
Uncertain
0.48
BayesDel_addAF
Benign
-0.0098
T
BayesDel_noAF
Uncertain
-0.070
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.45
T
Eigen
Benign
0.097
Eigen_PC
Benign
0.20
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.84
T
M_CAP
Benign
0.068
D
MetaRNN
Benign
0.37
T
MetaSVM
Uncertain
0.22
D
MutationAssessor
Benign
0.64
N
PhyloP100
5.7
PrimateAI
Uncertain
0.61
T
PROVEAN
Benign
-1.4
N
REVEL
Uncertain
0.49
Sift
Benign
0.33
T
Sift4G
Benign
0.25
T
Polyphen
0.33
B
Vest4
0.52
MutPred
0.38
Gain of ubiquitination at K248 (P = 0.0797)
MVP
0.92
MPC
0.26
ClinPred
0.42
T
GERP RS
4.3
Varity_R
0.55
gMVP
0.73
Mutation Taster
=69/31
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.070
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: rs754934082; hg19: chr7-143020455; API