chr7-143351845-C-T

Variant names:

• chr7-143351845-C-T
• rs760793323
• NM_000083.3:c.2847C>T

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_Strong BP6_Very_Strong BP7

The NM_000083.3(CLCN1):​c.2847C>T​(p.Gly949Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000039 in 1,613,546 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 Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. G949G) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000040 (0 hom.)
• Consequence: CLCN1 NM_000083.3 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -2.85
• Publications: 1 publications found

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

ACMG classification

Our verdict: Benign. The variant received -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).
• BP6: Variant 7-143351845-C-T is Benign according to our data. Variant chr7-143351845-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 447065.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-2.85 with no splicing effect.

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.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CLCN1	NM_000083.3	MANE Select	c.2847C>T	p.Gly949Gly	synonymous	Exon 23 of 23	NP_000074.3	P35523
	CLCN1	NR_046453.2		n.2802C>T		non_coding_transcript_exon	Exon 22 of 22

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CLCN1	ENST00000343257.7	TSL:1 MANE Select	c.2847C>T	p.Gly949Gly	synonymous	Exon 23 of 23	ENSP00000339867.2	P35523
	CLCN1	ENST00000650516.2		c.2847C>T	p.Gly949Gly	synonymous	Exon 23 of 23	ENSP00000498052.2	A0A3B3IU72
	CLCN1	ENST00000958857.1		c.2760C>T	p.Gly920Gly	synonymous	Exon 22 of 22	ENSP00000628916.1

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152120 Hom.: 0 Cov.: 32

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: 0.0000588

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000199 AC: 5 AN: 250896 AF XY: 0.0000221

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: 0.0000441

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000404 AC: 59 AN: 1461426 Hom.: 0 Cov.: 32 AF XY: 0.0000358 AC XY: 26 AN XY: 726908

African (AFR) AF: 0.0000299 AC: 1 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44708

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.0000504 AC: 2 AN: 39684

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5766

European-Non Finnish (NFE) AF: 0.0000432 AC: 48 AN: 1111622

Other (OTH) AF: 0.0000994 AC: 6 AN: 60376

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152120 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74300

African (AFR) AF: 0.00 AC: 0 AN: 41418

American (AMR) AF: 0.00 AC: 0 AN: 15274

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000588 AC: 4 AN: 68020

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000282 Hom.: 0

Bravo AF: 0.0000416

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	-	1	Congenital myotonia, autosomal recessive form;C2936781:Congenital myotonia, autosomal dominant form (1)
-	-	1	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	0.16
DANN	Benign	0.59
PhyloP100		-2.9

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs760793323; hg19: chr7-143048938; COSMIC: COSV58375645; COSMIC: COSV58375645;