rs876658135

chr22-28734610-T-TGCCCTGGGACTGTGAGGAGGA

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PM4

The NM_007194.4(CHEK2):c.111_112insTCCTCCTCACAGTCCCAGGGC(p.Ser31_Gly37dup) variant causes a inframe insertion change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: CHEK2 NM_007194.4 inframe_insertion
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.0320

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_007194.4.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHEK2	NM_007194.4	c.111_112insTCCTCCTCACAGTCCCAGGGC	p.Ser31_Gly37dup	inframe_insertion	2/15	ENST00000404276.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHEK2	ENST00000404276.6	c.111_112insTCCTCCTCACAGTCCCAGGGC	p.Ser31_Gly37dup	inframe_insertion	2/15	1	NM_007194.4	P2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 05, 2015

The c.91_111dup21 variant (also known as p.S31_G37DUP) located in coding exon 1 of the CHEK2 gene, results from an in-frame 21 nucleotide duplication between nucleotide positions 91 and 111. This results in the duplication of codons 31 to 37, located in the SQ/TQ cluster domain (Matsuoka S, et al. Proc. Natl. Acad. Sci. U.S.A. 2000 Sep; 97(19):10389-94). This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.004% (greater than 26000 alleles tested) in our clinical cohort. These amino acid positions are well conserved in available vertebrate species. Since supporting evidence is limited at this time, the clinical significance of c.91_111dup21 remains unclear. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 03, 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 create or strengthen a splice site. ClinVar contains an entry for this variant (Variation ID: 229673). 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 variant, c.91_111dup, results in the insertion of 7 amino acid(s) of the CHEK2 protein (p.Ser31_Gly37dup), but otherwise preserves the integrity of the reading frame. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs876658135; hg19: chr22-29130598;