chr22-28699839-T-C

Position:

• chr22-28699839-T-C

Variant summary

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

The NM_007194.4(CHEK2):​c.1007A>G​(p.Gln336Arg) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000000686 in 1,457,622 control chromosomes in the GnomAD database, with no homozygous occurrence. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CHEK2 NM_007194.4 missense, splice_region
• Scores: Splicing: ADA: 0.9993
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.76

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 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHEK2	NM_007194.4	c.1007A>G	p.Gln336Arg	missense_variant, splice_region_variant	9/15	ENST00000404276.6	NP_009125.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHEK2	ENST00000404276.6	c.1007A>G	p.Gln336Arg	missense_variant, splice_region_variant	9/15	1	NM_007194.4	ENSP00000385747	P2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1457622 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 725476

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.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 27, 2022

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 sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 964251). This variant has not been reported in the literature in individuals affected with CHEK2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamine, which is neutral and polar, with arginine, which is basic and polar, at codon 336 of the CHEK2 protein (p.Gln336Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.099
BayesDel_addAF	Benign	0.0025	T
BayesDel_noAF	Benign	-0.23
CADD	Uncertain	24
DANN	Uncertain	0.98
DEOGEN2	Benign	0.088	T;.;T;.;T;.;T;.;.;.;.;.
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.44
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.75	.;T;.;D;.;D;D;D;.;D;T;D
M_CAP	Benign	0.036	D
MetaRNN	Uncertain	0.47	T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.98	T
MutationAssessor	Benign	0.26	N;N;N;.;N;.;N;.;N;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;N;N
PrimateAI	Uncertain	0.52	T
PROVEAN	Benign	-0.45	N;N;N;.;N;N;.;N;N;N;.;N
REVEL	Benign	0.20
Sift	Benign	0.063	T;D;T;.;T;T;.;T;D;T;.;T
Sift4G	Benign	0.10	T;D;T;.;T;T;.;T;D;T;.;.
Polyphen		0.12	B;P;B;.;B;B;B;P;P;.;.;.
Vest4		0.55
MutPred		0.49		Loss of catalytic residue at Q336 (P = 0.0151);Loss of catalytic residue at Q336 (P = 0.0151);Loss of catalytic residue at Q336 (P = 0.0151);.;Loss of catalytic residue at Q336 (P = 0.0151);.;Loss of catalytic residue at Q336 (P = 0.0151);.;Loss of catalytic residue at Q336 (P = 0.0151);.;.;.;
MVP		0.90
MPC		0.050
ClinPred		0.89	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.40
gMVP		0.55

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.96
SpliceAI score (max)		0.050		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: rs1300388084; hg19: chr22-29095827;