22-28734663-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1PM2BP4_Moderate

The NM_007194.4(CHEK2):c.59A>G(p.Gln20Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000031 in 1,613,690 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q20H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

CHEK2
NM_007194.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 1.67

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 2 ACMG points.

PM1

In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 17 uncertain in NM_007194.4

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.21123621).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHEK2	NM_007194.4 linkuse as main transcript	c.59A>G	p.Gln20Arg	missense_variant	2/15	ENST00000404276.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHEK2	ENST00000404276.6 linkuse as main transcript	c.59A>G	p.Gln20Arg	missense_variant	2/15	1	NM_007194.4	P2	O96017-1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151926

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000242

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

GnomAD3 exomes

AF:

0.00000808

AC:

AN:

247598

Hom.:

AF XY:

0.0000149

AC XY:

AN XY:

134102

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:

0.0000181

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1461764

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727182

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:

0.00000360

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000658

AC:

AN:

151926

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74198

show subpopulations

Gnomad4 AFR

AF:

0.0000242

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

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Mar 26, 2020	Not observed at a significant frequency in large population cohorts (Lek 2016); In silico analysis supports that this missense variant does not alter protein structure/function; Absent from breast cancer cases but observed in control populations (Momozawa 2018); This variant is associated with the following publications: (PMID: 30287823) -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	May 23, 2018	- -

Hereditary cancer-predisposing syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Mar 05, 2024	The p.Q20R variant (also known as c.59A>G), located in coding exon 1 of the CHEK2 gene, results from an A to G substitution at nucleotide position 59. The glutamine at codon 20 is replaced by arginine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	May 10, 2021	This missense variant replaces glutamine with arginine at codon 20 of the CHEK2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 2/247598 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Sep 19, 2017

Variant summary: The c.59A>G (p.Gln20Arg) in CHEK2 gene is a missense variant involves a non-conserved nucleotide and 2/4 in silico tools predict benign outcome, however no functional studies supporting these predictions were published at the time of evaluation. The variant is located within the SQ/TQ cluster domain, although the functional impact of this change on protein remains unclear. The c.7984A>G is present in the control population datasets of ExAC and gnomAD at a low frequency of 0.000008 (2/ 242298 chrs tested), which does not exceed the maximum expected allele frequency for a pathogenic variant of 0.000028. To our knowledge, the variant has not been reported in affected individuals via published reports, but is cited as VUS by reputable databases/clinical laboratories. Taken together, the variant was classified as VUS, until new information becomes available. -

Familial cancer of breast

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 29, 2024

This sequence change replaces glutamine, which is neutral and polar, with arginine, which is basic and polar, at codon 20 of the CHEK2 protein (p.Gln20Arg). This variant is present in population databases (rs753257724, gnomAD 0.002%). 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: 232706). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.093

BayesDel_addAF

Pathogenic

0.23

BayesDel_noAF

Uncertain

0.11

Cadd

Benign

Dann

Uncertain

1.0

DEOGEN2

Benign

0.12

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

Eigen

Uncertain

0.19

Eigen_PC

Benign

0.13

FATHMM_MKL

Uncertain

0.84

M_CAP

Uncertain

0.12

MetaRNN

Benign

0.21

T;T;T;T;T;T;T;T;T;T;T;T;T

MetaSVM

Uncertain

0.40

MutationAssessor

Benign

1.9

L;L;L;L;L;L;L;L;.;.;.;.;.

MutationTaster

Benign

1.0

D;N;N;N;N;N;N;N;N;N;N

PrimateAI

Benign

0.39

PROVEAN

Benign

-0.63

N;N;N;N;N;.;N;N;N;N;N;.;N

REVEL

Benign

0.29

Sift

Uncertain

0.014

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

Sift4G

Pathogenic

0.0

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

Polyphen

0.97

D;D;D;D;P;D;D;D;.;.;.;.;.

Vest4

0.39

MutPred

0.16

Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);Gain of MoRF binding (P = 0.0208);

MVP

0.98

MPC

0.15

ClinPred

0.64

GERP RS

4.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.073

gMVP

0.14

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

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