22-28734445-A-G

Variant names:

• chr22-28734445-A-G
• rs730881697
• NM_007194.4:c.277T>C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_007194.4(CHEK2):​c.277T>C​(p.Trp93Arg) variant causes a missense change. The variant allele was found at a frequency of 0.0000041 in 1,461,784 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: 31)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: CHEK2 NM_007194.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:7
• Conservation: PhyloP100: 5.92

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.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.915

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHEK2	NM_007194.4	c.277T>C	p.Trp93Arg	missense_variant	Exon 2 of 15	ENST00000404276.6	NP_009125.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHEK2	ENST00000404276.6	c.277T>C	p.Trp93Arg	missense_variant	Exon 2 of 15	1	NM_007194.4	ENSP00000385747.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251224 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135814

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: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000410 AC: 6 AN: 1461784 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 727180

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: 0.00000450

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 31

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:3

Aug 28, 2024

Institute for Biomarker Research, Medical Diagnostic Laboratories, L.L.C.

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Trp93Arg variant is observed in 1/113,576 (0.0009%) alleles from individuals of gnomAD Non Finnish European background in gnomAD. The p.Trp93Arg variant is novel (not in any individuals) in 1kG. There is a moderate physicochemical difference between tryptophan and arginine. The p.Trp93Arg missense variant is predicted to be damaging by both SIFT and PolyPhen2. For these reasons, this variant has been classified as Uncertain Significance. -

Oct 03, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces tryptophan with arginine at codon 93 of the CHEK2 protein. . Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). This variant has been shown to impact function in a yeast DNA repair assay (PMID: 30851065) and in a kinase assay (PMID: 37449874). This variant has been reported in individuals affected with breast cancer (PMID: 32885271, 37449874), and in an unaffected individual (PMID: 33471991; Leiden Open Variation Database DB-ID CHEK2_000228). This variant has been identified in 1/251224 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. -

Apr 08, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.W93R variant (also known as c.277T>C), located in coding exon 1 of the CHEK2 gene, results from a T to C substitution at nucleotide position 277. The tryptophan at codon 93 is replaced by arginine, an amino acid with dissimilar properties. This variant was detected in an individual diagnosed with breast cancer at age 61 and 71 (Lerner-Ellis J et al. J Cancer Res Clin Oncol, 2021 Mar;147:871-879). This variant behaved as non-functional in an in vivo, yeast-based growth rate assay (Delimitsou A et al. Hum Mutat, 2019 05;40:631-648). This alteration was also 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. Based on the available evidence, the clinical significance of this variant remains unclear. -

not provided Uncertain:2

May 14, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 33298767, 32885271, 33471991, 37449874, 22419737, 19782031, 34326862, 30851065) -

Dec 29, 2017

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Malignant tumor of breast Uncertain:1

-

Department of Pathology and Laboratory Medicine, Sinai Health System

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

The CHEK2 p.Trp93Arg variant was not identified in the literature. The variant was identified in dbSNP (rs730881697) as “with uncertain significance allele” and ClinVar (classified as uncertain significance by Invitae, Color, Ambry Genetics and 2 other submitters). The variant was identified in control databases in 1 of 246,184 chromosomes at a frequency of 0.000004 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the European population in 1 of 111,672 chromosomes (freq: 0.000009), but not in the African, Other, Latino, Ashkenazi Jewish, East Asian, Finnish, or South Asian populations. A yeast-based functional assay showed that the variant had a damaging effect on cell function (Delimitsou 2019). The p.Trp93 residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information, the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Familial cancer of breast Uncertain:1

Jan 28, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces tryptophan, which is neutral and slightly polar, with arginine, which is basic and polar, at codon 93 of the CHEK2 protein (p.Trp93Arg). This variant is present in population databases (rs730881697, gnomAD 0.0009%). This missense change has been observed in individual(s) with breast cancer (PMID: 32885271, 34326862). ClinVar contains an entry for this variant (Variation ID: 182447). 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. Experimental studies have shown that this missense change affects CHEK2 function (PMID: 30851065, 37449874). 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	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.41
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.60	D;.;D;D;.;D;.;.;.;.;T;.;.
Eigen	Pathogenic	0.70
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Benign	0.80	.;T;.;.;T;T;T;.;T;T;T;T;T
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.91	D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.80	D
MutationAssessor	Uncertain	2.3	M;M;M;M;M;M;M;M;.;.;.;.;.
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-12	D;D;D;D;D;.;D;D;D;D;D;.;.
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	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		1.0	D;D;D;D;D;D;D;D;.;.;.;.;.
Vest4		0.81
MutPred		0.70		Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);Gain of disorder (P = 0.0037);
MVP		0.97
MPC		0.19
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.98
gMVP		0.63

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

Other links and lift over

dbSNP: rs730881697; hg19: chr22-29130433;