rs769933461

Variant names:

• chr22-28695225-G-A
• rs769933461
• NM_007194.4:c.1277C>T

Your query was ambiguous. Multiple possible variants found:

• chr22-28695225-G-A
• chr22-28695225-G-C
• chr22-28695225-G-T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_007194.4(CHEK2):​c.1277C>T​(p.Pro426Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. P426H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CHEK2 NM_007194.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.91
• Publications: 6 publications found

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 Gene-Disease associations (from GenCC):

• CHEK2-related cancer predisposition

  Inheritance: AD Classification: DEFINITIVE Submitted by: Ambry Genetics
• hereditary breast carcinoma

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen
• Li-Fraumeni syndrome 2

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• acute myeloid leukemia

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• hereditary nonpolyposis colon cancer

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• familial ovarian cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 16 uncertain in NM_007194.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHEK2	NM_007194.4	c.1277C>T	p.Pro426Leu	missense_variant	Exon 12 of 15	ENST00000404276.6	NP_009125.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHEK2	ENST00000404276.6	c.1277C>T	p.Pro426Leu	missense_variant	Exon 12 of 15	1	NM_007194.4	ENSP00000385747.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.87e-7 AC: 1 AN: 1454664 Hom.: 0 Cov.: 28 AF XY: 0.00000138 AC XY: 1 AN XY: 724116

African (AFR) AF: 0.00 AC: 0 AN: 33302

American (AMR) AF: 0.00 AC: 0 AN: 44690

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26082

East Asian (EAS) AF: 0.00 AC: 0 AN: 39648

South Asian (SAS) AF: 0.00 AC: 0 AN: 86066

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53390

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 9.04e-7 AC: 1 AN: 1105618

Other (OTH) AF: 0.00 AC: 0 AN: 60118

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Aug 30, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.P426L variant (also known as c.1277C>T), located in coding exon 11 of the CHEK2 gene, results from a C to T substitution at nucleotide position 1277. The proline at codon 426 is replaced by leucine, an amino acid with similar properties. 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. -

Familial cancer of breast Uncertain:1

Jul 09, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 426 of the CHEK2 protein (p.Pro426Leu). This variant is not present in population databases (gnomAD no frequency). 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: 862184). 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. 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 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	0.99
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Benign	0.37	T;.;T;.;T;.;T;.;.
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	.;D;.;D;.;D;D;D;.
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.30	T
MutationAssessor	Uncertain	2.4	M;.;M;.;M;.;M;.;.
PhyloP100		7.9
PrimateAI	Uncertain	0.60	T
PROVEAN	Pathogenic	-9.2	D;D;D;.;D;D;.;D;D
REVEL	Pathogenic	0.71
Sift	Pathogenic	0.0	D;D;D;.;D;D;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;.;D;D;.;D;D
Polyphen		1.0	D;D;D;.;D;D;D;D;D
Vest4		0.92
MutPred		0.94		Loss of disorder (P = 0.024);.;Loss of disorder (P = 0.024);.;Loss of disorder (P = 0.024);.;Loss of disorder (P = 0.024);.;.;
MVP		0.84
MPC		0.17
ClinPred		1.0	D
GERP RS		5.8
Varity_R		0.99
gMVP		0.92
Mutation Taster		=19/81	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.19		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs769933461; hg19: chr22-29091213; COSMIC: COSV60426362;