Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1PM5PP2PP3_StrongPP5_Very_Strong

The NM_000083.3(CLCN1):c.871G>A(p.Glu291Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,992 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E291Q) has been classified as Likely pathogenic.

Frequency

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

Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

CLCN1
NM_000083.3 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 9.99

Publications

13 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

CLCN1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 17 ACMG points.

PM1

In a hotspot region, there are 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000083.3

PM5

Other missense variant is known to change same aminoacid residue: Variant chr7-143330789-G-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 3759127.Status of the report is criteria_provided_single_submitter, 1 stars.

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, 0.989

PP5

Variant 7-143330789-G-A is Pathogenic according to our data. Variant chr7-143330789-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 17541.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CLCN1	NM_000083.3	MANE Select	c.871G>A	p.Glu291Lys	missense	Exon 8 of 23	NP_000074.3
	CLCN1	NR_046453.2		n.976G>A		non_coding_transcript_exon	Exon 8 of 22

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
CLCN1	ENST00000343257.7	TSL:1 MANE Select	c.871G>A	p.Glu291Lys	missense	Exon 8 of 23	ENSP00000339867.2
CLCN1	ENST00000432192.6	TSL:1	n.*156G>A		non_coding_transcript_exon	Exon 8 of 23	ENSP00000395949.2
CLCN1	ENST00000455478.6	TSL:1	n.*156G>A		non_coding_transcript_exon	Exon 7 of 7	ENSP00000400027.2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152126

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000398

AC:

AN:

251366

AF XY:

0.00

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:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000410

AC:

AN:

1461866

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727236

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.0000116

AC:

AN:

86254

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53416

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5756

European-Non Finnish (NFE)

AF:

0.00000450

AC:

AN:

1112006

Other (OTH)

AF:

0.00

AC:

AN:

60394

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.492

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000131

AC:

AN:

152126

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74318

show subpopulations

African (AFR)

AF:

0.0000241

AC:

AN:

41418

American (AMR)

AF:

0.00

AC:

AN:

15260

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3468

East Asian (EAS)

AF:

0.00

AC:

AN:

5200

South Asian (SAS)

AF:

0.000207

AC:

AN:

4824

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10612

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68026

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.400

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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:

0.00

Hom.:

Bravo

AF:

0.00000756

ClinVar

ClinVar submissions as Germline

Significance:Pathogenic/Likely pathogenic

Revision:criteria provided, multiple submitters, no conflicts

View on ClinVar

Pathogenic

VUS

Benign

Condition

not provided (3)

Congenital myotonia, autosomal dominant form (2)

Congenital myotonia, autosomal recessive form (2)

Congenital myotonia, autosomal recessive form;C2936781:Congenital myotonia, autosomal dominant form (2)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

1.0

BayesDel_addAF

Pathogenic

0.56

BayesDel_noAF

Pathogenic

0.57

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.96

Eigen

Pathogenic

0.98

Eigen_PC

Pathogenic

0.86

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Pathogenic

1.0

M_CAP

Pathogenic

0.83

MetaRNN

Pathogenic

0.99

MetaSVM

Pathogenic

0.99

MutationAssessor

Pathogenic

4.5

PhyloP100

PrimateAI

Pathogenic

0.94

PROVEAN

Uncertain

-3.7

REVEL

Pathogenic

0.98

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Polyphen

1.0

Vest4

0.99

MutPred

0.96

Gain of MoRF binding (P = 0.0184)

MVP

0.99

MPC

0.79

ClinPred

1.0

GERP RS

4.6

Varity_R

0.98

gMVP

0.99

Mutation Taster

=0/100

disease causing (ClinVar)

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

NM_000083.3:c.871G>A

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

ClinVar submissions as Germline

Computational scores

Splicing

Publications

Other links and lift over