chr22-28694078-T-C

Position:

• chr22-28694078-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_007194.4(CHEK2):​c.1415A>G​(p.Lys472Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000693 in 1,443,838 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict 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. K472E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CHEK2 NM_007194.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:6
• Conservation: PhyloP100: 2.89

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 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 1 benign, 16 uncertain in NM_007194.4
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.21157).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHEK2	NM_007194.4	c.1415A>G	p.Lys472Arg	missense_variant	13/15	ENST00000404276.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHEK2	ENST00000404276.6	c.1415A>G	p.Lys472Arg	missense_variant	13/15	1	NM_007194.4	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.93e-7 AC: 1 AN: 1443838 Hom.: 0 Cov.: 30 AF XY: 0.00000139 AC XY: 1 AN XY: 718672

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:4

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Aug 01, 2022	This missense variant replaces lysine with arginine at codon 472 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 not been identified 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. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Sep 25, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneKor MSA	Aug 01, 2018	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 15, 2023	The p.K472R variant (also known as c.1415A>G), located in coding exon 12 of the CHEK2 gene, results from an A to G substitution at nucleotide position 1415. The lysine at codon 472 is replaced by arginine, an amino acid with highly similar properties. This alteration was reported as functional 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 tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 13, 2016

This variant is denoted CHEK2 c.1415A>G at the cDNA level, p.Lys472Arg (K472R) at the protein level, and results in the change of a Lysine to an Arginine (AAG>AGG). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. CHEK2 Lys472Arg was not observed in approximately 3,700 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. Since Lysine and Arginine share similar properties, this is considered a conservative amino acid substitution. CHEK2 Lys472Arg occurs at a position that is not conserved and is located within the protein kinase domain (Desrichard 2011, Roeb 2012). In silico analyses are inconsistent regarding the effect this variant may have on protein structure and function. Based on currently available information, it is unclear whether CHEK2 Lys472Arg is pathogenic or benign. We consider it to be a variant of uncertain significance. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 17, 2023

This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 472 of the CHEK2 protein (p.Lys472Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with personal and/or family history of breast and/or ovarian cancer (PMID: 31159747). ClinVar contains an entry for this variant (Variation ID: 418901). 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	0.071
BayesDel_addAF	Benign	-0.094	T
BayesDel_noAF	Benign	-0.37
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Benign	0.10	T;.;T;.;T;.;T;.;.
Eigen	Benign	0.10
Eigen_PC	Uncertain	0.22
FATHMM_MKL	Benign	0.70	D
LIST_S2	Benign	0.76	.;T;.;T;.;T;T;T;.
M_CAP	Benign	0.023	T
MetaRNN	Benign	0.21	T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.97	L;.;L;.;L;.;L;.;.
MutationTaster	Benign	0.55	D;D;D;D;D;D;D;D;N;N;N
PrimateAI	Benign	0.37	T
PROVEAN	Benign	-1.3	N;N;N;.;N;N;.;N;N
REVEL	Benign	0.077
Sift	Benign	0.15	T;T;T;.;T;T;.;T;T
Sift4G	Benign	0.17	T;T;T;.;T;T;.;T;T
Polyphen		0.11	B;P;B;.;B;B;B;P;P
Vest4		0.42
MutPred		0.32		Loss of ubiquitination at K472 (P = 0.0255);.;Loss of ubiquitination at K472 (P = 0.0255);.;Loss of ubiquitination at K472 (P = 0.0255);.;Loss of ubiquitination at K472 (P = 0.0255);.;.;
MVP		0.76
MPC		0.051
ClinPred		0.67	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.19
gMVP		0.21

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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

Other links and lift over

dbSNP: rs1064793511; hg19: chr22-29090066;