2-47160771-GGTCTTCACTTTGCT-G

Position:

• chr2-47160771-GGTCTTCACTTTGCT-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_001743.6(CALM2):​c.441_*4del variant causes a stop lost, 3 prime UTR change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: CALM2 NM_001743.6 stop_lost, 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.32

Genes affected

CALM2 (HGNC:1445): (calmodulin 2) This gene is a member of the calmodulin gene family. There are three distinct calmodulin genes dispersed throughout the genome that encode the identical protein, but differ at the nucleotide level. Calmodulin is a calcium binding protein that plays a role in signaling pathways, cell cycle progression and proliferation. Several infants with severe forms of long-QT syndrome (LQTS) who displayed life-threatening ventricular arrhythmias together with delayed neurodevelopment and epilepsy were found to have mutations in either this gene or another member of the calmodulin gene family (PMID:23388215). Mutations in this gene have also been identified in patients with less severe forms of LQTS (PMID:24917665), while mutations in another calmodulin gene family member have been associated with catecholaminergic polymorphic ventricular tachycardia (CPVT)(PMID:23040497), a rare disorder thought to be the cause of a significant fraction of sudden cardiac deaths in young individuals. Pseudogenes of this gene are found on chromosomes 10, 13, and 17. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Mar 2015]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PVS1: Stoplost variant. No alternative stopcodon identified downstream, so we assume a Nonstop Mediated Decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CALM2	NM_001743.6	c.441_*4del		stop_lost, 3_prime_UTR_variant	6/6	ENST00000272298.12	NP_001734.1
CALM2	NM_001305624.1	c.585_*4del		stop_lost, 3_prime_UTR_variant	7/7		NP_001292553.1
CALM2	NM_001305625.2	c.333_*4del		stop_lost, 3_prime_UTR_variant	6/6		NP_001292554.1
CALM2	NM_001305626.1	c.333_*4del		stop_lost, 3_prime_UTR_variant	5/5		NP_001292555.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CALM2	ENST00000272298.12	c.441_*4del		stop_lost, 3_prime_UTR_variant	6/6	1	NM_001743.6	ENSP00000272298	P1

Frequencies

GnomAD3 genomes Cov.: 31

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Long QT syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 31, 2024

This sequence change results in a frameshift in the CALM2 gene (p.Ala148Leufs*6). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 2 amino acid(s) of the CALM2 protein and extend the protein by 3 additional amino acid residues. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CALM2-related conditions. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr2-47387910;