chr7-143346211-G-C

Position:

• chr7-143346211-G-C

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_000083.3(CLCN1):​c.2244G>C​(p.Leu748Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. L748L) has been classified as Benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: CLCN1 NM_000083.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.89

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 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.54).
• BP7: Synonymous conserved (PhyloP=1.89 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CLCN1	NM_000083.3	c.2244G>C	p.Leu748Leu	synonymous_variant	18/23	ENST00000343257.7	NP_000074.3
CLCN1	NR_046453.2	n.2199G>C		non_coding_transcript_exon_variant	17/22

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CLCN1	ENST00000343257.7	c.2244G>C	p.Leu748Leu	synonymous_variant	18/23	1	NM_000083.3	ENSP00000339867.2
CLCN1	ENST00000432192.6	n.*1529G>C		non_coding_transcript_exon_variant	18/23	1		ENSP00000395949.2
CLCN1	ENST00000432192.6	n.*1529G>C		3_prime_UTR_variant	18/23	1		ENSP00000395949.2
CLCN1	ENST00000650516.2	c.2244G>C	p.Leu748Leu	synonymous_variant	18/23			ENSP00000498052.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.54
CADD	Benign	3.9
DANN	Benign	0.73

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs78085922; hg19: chr7-143043304;