22-28696963-G-A

Position:

chr22-28696963-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PP3_Strong

The NM_007194.4(CHEK2):c.1033C>T(p.His345Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000158 in 1,460,156 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

CHEK2
NM_007194.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts P:1U:9

Conservation

PhyloP100: 7.84

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 Uncertain_significance. Variant got 4 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.977

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHEK2	NM_007194.4 linkuse as main transcript	c.1033C>T	p.His345Tyr	missense_variant	10/15	ENST00000404276.6	NP_009125.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHEK2	ENST00000404276.6 linkuse as main transcript	c.1033C>T	p.His345Tyr	missense_variant	10/15	1	NM_007194.4	ENSP00000385747	P2	O96017-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251194

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135780

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:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000158

AC:

AN:

1460156

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

726522

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:

0.0000207

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000468

Hom.:

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1Uncertain:9

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Familial cancer of breast

Uncertain:4

Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	Feb 20, 2018	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 05, 2022	This sequence change replaces histidine, which is basic and polar, with tyrosine, which is neutral and polar, at codon 345 of the CHEK2 protein (p.His345Tyr). This variant is present in population databases (no rsID available, gnomAD 0.0009%). 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: 220465). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Oct 11, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Mar 08, 2023	This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -

Hereditary cancer-predisposing syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 08, 2023	The p.H345Y variant (also known as c.1033C>T), located in coding exon 9 of the CHEK2 gene, results from a C to T substitution at nucleotide position 1033. The histidine at codon 345 is replaced by tyrosine, an amino acid with similar properties. This alteration has been reported in both breast and/or ovarian cancer cohort patients, as well as unaffected control individuals across studies (Decker B et al. J Med Genet, 2017 Nov;54:732-741; Dorling et al. N Engl J Med 2021 02;384:428-439; Hauke J et al. Cancer Med, 2018 Apr;7:1349-1358; Song H et al. J Med Genet, 2021 May;58:305-313). This alteration was reported as functionally impaired in a study assessing CHEK2-complementation through quantification of KAP1 phosphorylation and CHK2 autophosphorylation in human RPE1-CHEK2-knockout cells (Stolarova L et al. Clin Cancer Res, 2023 Aug;29:3037-3050). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Feb 08, 2019	- -

Li-Fraumeni syndrome 2

Pathogenic:1

Likely pathogenic, no assertion criteria provided

clinical testing

Department of Genetics, HCU Lozano Blesa

May 01, 2023

Variant summary: CHEK2 c.1033C>T results in the replacement of His345 by a Tyr residue (p.His345Tyr). The variant was identified in 1 out of 396 patients analysed (freq: 0.0025, doi: 10.3389/fgene.2023.1274108). The patient was a woman that developed breast cancer at the age of 38 years (luminal-B tumor phenotype). One first-degree relative of her was also diagnosed with BC, although a co-segregation study could not be performed. His345 is located in the kinase domain, and is part of the well-conserved motif HRD (His345–Arg-346–Asp347) in the catalytic loop of the protein. In this motif, His345 establishes an H-bond with the key catalytic residue Asp347. Thus, its replacement by a Tyr residue (bulkier) may detrimentally affect the catalytic activity of the protein. In addition, His345 forms a fair H-bond (~2.7 Å) with the backbone of Asp368, located in the activation T-loop crucial for homodimerization. The variant is reported in gnomAD v4 in 23 cases out of 1460156 alleles analysed (freq=1.6x10-3 %). In ClinVar 8 reports appear classifying the variant as of Uncertain significance. Other replacements found at this position (H345Q, H345P, H345R, H345L, and H345D) are also classified by ClinVar as of Uncertain Significance. The metapredictor PirePred (relies on verdicts from other 15 predictor or metapredictor tools) and the AI-based predictor AlphaMissense classify His345Tyr as Pathogenic, whereas the ACMG classification tool Franklin suggests this variant as VUS (Uncertain Significance). Our in-silico study on the protein stability based on relaxation molecular dynamics simulations (doi: 10.3389/fgene.2023.1274108) indicates that His345Tyr induces conformational unstability on CHEK2 protein. Moreover, Stolarova L. et al’s functional study on KAP1 phosphorylation and CHEK2 autophosphorylation protein capability reports this variant as functionally impaired (PMID: 37449874). With all this information, we believe this variant have more chances of being Pathogenic. -

Breast and/or ovarian cancer

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Jun 15, 2021

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 26, 2019

Not observed at a significant frequency in large population cohorts (Lek 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Hereditary breast ovarian cancer syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

curation

German Consortium for Hereditary Breast and Ovarian Cancer, University Hospital Cologne

Jun 11, 2024

BRIDGES 2X in 60466 cases and 2X in 53461 controls; 2X in GC-HBOC database; According to the ACMG SVI adaptation criteria we chose these criteria: PS3 (medium pathogenic): Stolarova 2023: KAP1: impaired (0,081); CHK2 impaired (0,457), PM2 (supporting pathogenic): n=1 in gnomAD v2, absent in v3, PP3 (supporting pathogenic): Revel 0.914 -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.98

BayesDel_addAF

Pathogenic

0.43

BayesDel_noAF

Pathogenic

0.37

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.37

T;T;.;T;.;T;.;.;.

Eigen

Pathogenic

0.95

Eigen_PC

Pathogenic

0.90

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.98

.;.;D;.;D;D;D;D;D

M_CAP

Uncertain

0.14

MetaRNN

Pathogenic

0.98

D;D;D;D;D;D;D;D;D

MetaSVM

Uncertain

0.53

MutationAssessor

Pathogenic

3.0

M;M;.;M;.;M;.;.;.

MutationTaster

Benign

1.0

D;D;D;D;D;D;D;D;D;D;D

PrimateAI

Pathogenic

0.86

PROVEAN

Pathogenic

-5.7

D;D;.;D;D;.;D;D;.

REVEL

Pathogenic

0.91

Sift

Pathogenic

0.0

D;D;.;D;D;.;D;D;.

Sift4G

Pathogenic

0.0

D;D;.;D;D;.;D;D;.

Polyphen

1.0

D;D;.;D;D;D;D;.;.

Vest4

0.96

MutPred

0.92

Loss of disorder (P = 0.0636);Loss of disorder (P = 0.0636);.;Loss of disorder (P = 0.0636);.;Loss of disorder (P = 0.0636);.;.;.;

MVP

0.97

MPC

0.17

ClinPred

1.0

GERP RS

5.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.98

gMVP

0.90

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

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

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