chr22-28695187-G-C

Position:

• chr22-28695187-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_007194.4(CHEK2):​c.1315C>G​(p.Gln439Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,190 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: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CHEK2 NM_007194.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 7.91

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 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.746

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHEK2	NM_007194.4	c.1315C>G	p.Gln439Glu	missense_variant	12/15	ENST00000404276.6	NP_009125.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHEK2	ENST00000404276.6	c.1315C>G	p.Gln439Glu	missense_variant	12/15	1	NM_007194.4	ENSP00000385747.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251024 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135642

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: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461190 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726954

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Li-Fraumeni syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

KCCC/NGS Laboratory, Kuwait Cancer Control Center

Apr 03, 2024

This sequence change replaces glutamine, which is neutral and polar, with glutamic acid, which is acidic and polar, at codon 439 of the CHEK2 protein (p.Gln439Glu). This variant is present in population databases (rs778989252, gnomAD 0.003%). 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: 460800). Computational prediction suggests that this variant may not impact protein structure and function. Functional studies have not been reported for this variant. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Feb 26, 2021

This missense variant replaces glutamine with glutamic acid at codon 439 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 1/251024 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. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 09, 2023

This sequence change replaces glutamine, which is neutral and polar, with glutamic acid, which is acidic and polar, at codon 439 of the CHEK2 protein (p.Gln439Glu). 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. 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. ClinVar contains an entry for this variant (Variation ID: 460800). This variant has not been reported in the literature in individuals affected with CHEK2-related conditions. This variant is present in population databases (rs778989252, gnomAD 0.003%). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.55
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	0.060
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Benign	0.25	T;.;T;.;T;.;T;.;.
Eigen	Pathogenic	0.72
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.91	.;D;.;D;.;D;D;D;.
M_CAP	Benign	0.055	D
MetaRNN	Pathogenic	0.75	D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.40	T
MutationAssessor	Benign	1.2	L;.;L;.;L;.;L;.;.
PrimateAI	Benign	0.47	T
PROVEAN	Uncertain	-2.7	D;D;D;.;D;D;.;D;D
REVEL	Uncertain	0.45
Sift	Uncertain	0.0020	D;D;D;.;D;D;.;D;D
Sift4G	Uncertain	0.011	D;D;D;.;D;D;.;D;D
Polyphen		1.0	D;D;D;.;D;D;D;D;D
Vest4		0.78
MutPred		0.62		Gain of disorder (P = 0.1035);.;Gain of disorder (P = 0.1035);.;Gain of disorder (P = 0.1035);.;Gain of disorder (P = 0.1035);.;.;
MVP		0.91
MPC		0.14
ClinPred		0.86	D
GERP RS		5.8
Varity_R		0.93
gMVP		0.79

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: rs778989252; hg19: chr22-29091175;