22-28699852-G-C

Position:

• chr22-28699852-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_007194.4(CHEK2):​c.994C>G​(p.Leu332Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. L332F) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: CHEK2 NM_007194.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 5.46

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.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHEK2	NM_007194.4	c.994C>G	p.Leu332Val	missense_variant	9/15	ENST00000404276.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHEK2	ENST00000404276.6	c.994C>G	p.Leu332Val	missense_variant	9/15	1	NM_007194.4	P2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 25, 2024	The p.L332V variant (also known as c.994C>G), located in coding exon 8 of the CHEK2 gene, results from a C to G substitution at nucleotide position 994. The leucine at codon 332 is replaced by valine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. 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	Oct 07, 2021	This missense variant replaces leucine with valine at codon 332 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. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 11, 2017

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. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with CHEK2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with valine at codon 332 of the CHEK2 protein (p.Leu332Val). The leucine residue is highly conserved and there is a small physicochemical difference between leucine and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.27
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.030
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.11	T;.;T;.;T;.;T;.;.;.;.;.
Eigen	Benign	0.14
Eigen_PC	Uncertain	0.31
FATHMM_MKL	Pathogenic	0.97	D
M_CAP	Benign	0.024	T
MetaRNN	Uncertain	0.57	D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.99	L;L;L;.;L;.;L;.;L;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.76	T
PROVEAN	Benign	-0.33	N;N;N;.;N;N;.;N;N;N;.;N
REVEL	Benign	0.20
Sift	Benign	0.50	T;T;T;.;T;T;.;T;T;T;.;T
Sift4G	Benign	0.63	T;T;T;.;T;T;.;T;T;T;.;.
Polyphen		0.41	B;P;B;.;B;B;B;P;P;.;.;.
Vest4		0.71
MutPred		0.69		Gain of MoRF binding (P = 0.3734);Gain of MoRF binding (P = 0.3734);Gain of MoRF binding (P = 0.3734);.;Gain of MoRF binding (P = 0.3734);.;Gain of MoRF binding (P = 0.3734);.;Gain of MoRF binding (P = 0.3734);.;.;.;
MVP		0.62
MPC		0.023
ClinPred		0.65	D
GERP RS		5.7
Varity_R		0.51
gMVP		0.56

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: rs1555915348; hg19: chr22-29095840;