22-28734402-C-T

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_007194.4(CHEK2):c.319+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000205 in 1,461,524 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: not found (cov: 31)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

CHEK2
NM_007194.4 splice_donor, intron

Scores

Splicing: ADA: 1.000

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 5.01

Variant links:

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]

CHEK2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 22-28734402-C-T is Pathogenic according to our data. Variant chr22-28734402-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 481726.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHEK2	NM_007194.4 link	c.319+1G>A		splice_donor_variant, intron_variant	Intron 2 of 14	ENST00000404276.6	NP_009125.1	O96017-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHEK2	ENST00000404276.6 link	c.319+1G>A		splice_donor_variant, intron_variant	Intron 2 of 14	1	NM_007194.4	ENSP00000385747.1		O96017-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000797

AC:

AN:

250812

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135656

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 SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000883

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461524

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727074

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.00000378

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:8

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Familial cancer of breast

Pathogenic:4

Apr 02, 2020

Department of Molecular Diagnostics, Institute of Oncology Ljubljana

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 17, 2023

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Sep 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 2 of the CHEK2 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in CHEK2 are known to be pathogenic (PMID: 21876083, 24713400). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with CHEK2-related conditions. ClinVar contains an entry for this variant (Variation ID: 481726). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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. -

Jun 23, 2023

Myriad Genetics, Inc.

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely pathogenic. This variant occurs within a consensus splice junction and is predicted to result in abnormal mRNA splicing of either an out-of-frame exon or an in-frame exon necessary for protein stability and/or normal function. -

Hereditary cancer-predisposing syndrome

Pathogenic:2

Mar 16, 2020

Color Diagnostics, LLC DBA Color Health

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant causes a G to A nucleotide substitution at the +1 position of intron 2 of the CHEK2 gene. Splice site prediction tools predict that this variant may have a significant impact on RNA splicing. Although RNA studies have not been reported for this variant, this variant is expected to result in an absent or non-functional protein product. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 2/250812 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss of CHEK2 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Likely Pathogenic. -

Jan 08, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.319+1G>A intronic variant results from a G to A substitution one nucleotide after coding exon 1 of the CHEK2 gene. This nucleotide position is highly conserved in available vertebrate species. In silico splice site analysis predicts that this alteration will weaken the native splice donor site. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. As such, this alteration is classified as likely pathogenic. -

CHEK2-related disorder

Pathogenic:1

Jul 12, 2024

PreventionGenetics, part of Exact Sciences

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

The CHEK2 c.319+1G>A variant is predicted to disrupt the GT donor site and interfere with normal splicing. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0033% of alleles in individuals of South Asian descent in gnomAD and is interpreted as pathogenic/likely pathogenic in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/481726/). Variants that disrupt the consensus splice donor site in CHEK2 are expected to be pathogenic. This variant is interpreted as likely pathogenic. -

Breast cancer, susceptibility to;C3469524:Prostate cancer susceptibility

Pathogenic:1

Oct 23, 2019

Human Genome Sequencing Center Clinical Lab, Baylor College of Medicine

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.319+1G>A variant occurs in the donor splice site of intron 2 of the CHEK2 gene and is predicted to affect splicing, likely resulting in disrupted or absent protein product via nonsense mediated decay. While this particular variant has not been reported in individuals with CHEK2-related cancer, a different variant also at the same donor splice site (c.319+2T>A) is associated with thyroid cancer, breast cancer, and colorectal cancer (PMID: 28608266, 26681312, 27696107). The c.319+1G>A variant is very rare in population databases (2/250812 alleles in gnomAD). Loss-of-function variants in CHEK2 are considered pathogenic (PMID: 21876083, 24713400). This variant has been classified as Likely Pathogenic, however due to low allele fraction detected on NGS in this sample, this could represent somatic mosaicism. The clinical significance of this finding warrants further investigation. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.45

BayesDel_noAF

Pathogenic

0.41

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.96

FATHMM_MKL

Uncertain

0.95

GERP RS

5.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.8

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.94

SpliceAI score (max)

1.0

Details are displayed if max score is > 0.2

DS_DL_spliceai

1.0

Position offset: 1

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over