rs587782707

Positions:

• chr22-28689173-C-CCT

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The ENST00000404276.6(CHEK2):​c.1503_1504insAG​(p.Glu502ArgfsTer12) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,158 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. E501E) has been classified as Likely benign.

• Frequency: Genomes: 𝑓 0.000013 (0 hom., cov: 32)
• Consequence: CHEK2 ENST00000404276.6 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 0.541

Genes affected

CHEK2 (HGNC:16627): (checkpoint kinase 2) In response to DNA damage and replication blocks, cell cycle progression is halted through the control of critical cell cycle regulators. The protein encoded by this gene is a cell cycle checkpoint regulator and putative tumor suppressor. It contains a forkhead-associated protein interaction domain essential for activation in response to DNA damage and is rapidly phosphorylated in response to replication blocks and DNA damage. When activated, the encoded protein is known to inhibit CDC25C phosphatase, preventing entry into mitosis, and has been shown to stabilize the tumor suppressor protein p53, leading to cell cycle arrest in G1. In addition, this protein interacts with and phosphorylates BRCA1, allowing BRCA1 to restore survival after DNA damage. Mutations in this gene have been linked with Li-Fraumeni syndrome, a highly penetrant familial cancer phenotype usually associated with inherited mutations in TP53. Also, mutations in this gene are thought to confer a predisposition to sarcomas, breast cancer, and brain tumors. This nuclear protein is a member of the CDS1 subfamily of serine/threonine protein kinases. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. There are 13 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 22-28689173-C-CCT is Pathogenic according to our data. Variant chr22-28689173-C-CCT is described in ClinVar as [Likely_pathogenic]. Clinvar id is 142772.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHEK2	NM_007194.4	c.1503_1504insAG	p.Glu502ArgfsTer12	frameshift_variant	14/15	ENST00000404276.6	NP_009125.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHEK2	ENST00000404276.6	c.1503_1504insAG	p.Glu502ArgfsTer12	frameshift_variant	14/15	1	NM_007194.4	ENSP00000385747	P2

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152158 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000483

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 29

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152158 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74324

Gnomad4 AFR AF: 0.0000483

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000151

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Pathogenic:3

Likely pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Oct 28, 2021	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 29, 2023	This sequence change creates a premature translational stop signal (p.Glu502Argfs*12) in the CHEK2 gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 42 amino acid(s) of the CHEK2 protein. This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with breast cancer (PMID: 32427313). ClinVar contains an entry for this variant (Variation ID: 142772). This variant disrupts the nuclear localization signal (NLS) of the CHEK2 protein, which is critical for proper nuclear localization (PMID: 18004398, 12909615). While functional studies have not been performed to directly test the effect of this variant on CHEK2 protein function, this suggests that disruption of this region of the protein is causative of disease. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Jun 29, 2023	This variant is considered pathogenic. This variant creates a frameshift predicted to result in premature protein truncation. -

Hereditary cancer-predisposing syndrome Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Oct 06, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 14, 2023	The c.1502_1503dupAG pathogenic mutation, located in coding exon 13 of the CHEK2 gene, results from a duplication of AG at nucleotide positions 1502 to 1503, causing a translational frameshift with a predicted alternate stop codon (p.E502Rfs*12). This alteration occurs at the 3' terminus of theCHEK2 gene, is not expected to trigger nonsense-mediated mRNA decay, and only impacts the last 7.7% of the protein. However, premature stop codons are typically deleterious in nature and a significant portion of the protein is affected (Ambry internal data). This alteration was identified amongst multiple cohorts of African American prostate and breast cancer patients (Ademuyiwa FO et al. Breast Cancer Res Treat, 2019 Nov;178:151-159; Palmer JR et al. J Natl Cancer Inst, 2020 Dec;112:1213-1221; Trendowski MR et al. JCO Precis Oncol, 2022 Nov;6:e2200460). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs587782707; hg19: chr22-29085161;