About CHEK2
No gene-level summary was recorded for this case.
No variant summary was recorded for this case.
Five-step scale from benign to pathogenic. This variant is uncertain. Select a step to read what it means.
Uncertain.The recorded classification is uncertain significance.
Gene-level background from the recorded interpretation.
Words with a dotted underline have a short definition. Hover or tap them.No gene-level summary was recorded for this case.
The recorded framework is ClinGen CHEK2 VCEP v1.0. The criteria and strengths shown below come from the saved assessment; this page does not recalculate the classification.
The applied criteria and their strengths are shown as assessed under the stated framework.
NM_007194.4:c.58C>T is a nonsense variant (p.Gln20Ter) in exon 2 of 15, resulting in premature termination at amino acid 20 of 544. This abolishes the entire protein product including the SQ/TQ-rich domain (residues 20-75), forkhead-associated domain (residues 115-165), and kinase domain (residues 225-490). NMD is predicted. CHEK2 loss of function is an established disease mechanism for CHEK2-related cancer predisposition (autosomal dominant). Under ClinGen SVI PVS1 recommendations (PMC6185798), a null variant in a gene where LoF is a known mechanism qualifies for PVS1 at very strong strength.
This variant is present at very low frequency in population databases. gnomAD v4.1 reports an overall allele frequency of 0.0063% (102/1,613,966 alleles, 0 homozygotes). gnomAD v2.1 reports 0.014% (35/247,462 alleles, 0 homozygotes). The highest subpopulation frequency is in South Asian: 0.111% (gnomAD v4.1), still below 0.1% for the masking filter (grpmax FAF 0.093%). Overall frequency is well below the 0.1% threshold, supporting PM2 at supporting strength.
No benign criterion marked as applied in the recorded assessment.
ClinGen Hereditary Breast, Ovarian and Pancreatic Cancer Expert Panel Specifications to the ACMG/AMP Variant Interpretation Guidelines for CHEK2 Version 1.0 v1.0 lacked a usable explicit final combination framework, so generic ACMG/AMP 2015 final-combination rules were applied as fallback; applied criteria: PVS1 very strong, PM2 supporting; combination = 1 very strong + 1 supporting, which maps to VUS.
Evidence summaries and captured source records, where available. Missing entries should not be interpreted as negative findings.
gnomAD v4.1: 102 / 1,613,966 alleles. Recorded AF 6.31984e-05. Recorded homozygote count 0.
This variant is present in gnomAD v2.1 (AF= 0.000141436; MAF= 0.01414%, 35/247462 alleles, homozygotes = 0) and has highest observed frequency in the South Asian population (AF= 0.00114589; MAF= 0.11459%, 35/30544 alleles, homozygotes = 0); grpmax FAF= 0.00084634.
Not available in gnomAD-Canada v1.0.
Recorded SpliceAI maximum delta score: 0.040. Refer to the recorded PP3/BP4 rationale for interpretation.
15 Pathogenic · 3 Likely pathogenic · 1 Uncertain significance · 1 Likely Pathogenic · 1 pathogenic. ClinVar API review status: criteria provided, multiple submitters, no conflicts.
OncoKB identified variant-specific curated literature and context relevant to functional review; biological-effect context: Likely Loss-of-function; curated oncogenicity label: Likely Oncogenic.
This variant has not previously been reported in somatic cancers (COSMIC).
This variant does not lie in a statistically significant hotspot.
ACMG/AMP criteria under ClinGen CHEK2 VCEP v1.0, with the data and sources behind each one.
29 criteria with recorded statuses: 2 met · 18 not met · 0 not assessed · 9 not applicable. Open any row for the full reasoning, the rule and the evidence behind it.
NM_007194.4:c.58C>T (p.Gln20Ter) is a nonsense variant in exon 2 of 15 of CHEK2, predicted to trigger NMD and abolish essentially the entire protein product including the SQ/TQ-rich, FHA, and kinase domains. CHEK2 loss of function is an established mechanism for autosomal dominant cancer predisposition.
This variant is observed at extremely low frequency in population databases: gnomAD v4.1 reports an overall allele frequency of 0.0063% (102/1,613,966 alleles, 0 homozygotes) and v2.1 reports 0.014% (35/247,462 alleles).
ClinVar classifies this variant as Pathogenic (ClinVarID 133887, 1-star review status), with 15 clinical laboratories reporting as Pathogenic and 3 as Likely Pathogenic.
One confirmed published case in a 48-year-old female with ER+/PR+/HER2+ invasive ductal breast carcinoma, identified among 7,657 Chinese BRCA1/2-negative breast cancer patients in Fan et al. (2018, PMID:29356917).
OncoKB classifies this variant as Likely Oncogenic and predicts Likely Loss-of-function based on the truncating nature of the variant.
No criteria match.
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Every interpreted variant in CHEK2, mapped onto the exon structure of NM_007194.4. Select a row to find it on the plot.
| Protein | Location | Classification | Link |
|---|
| South Asian101 / 91,068 | 0.0011 |
| Middle Eastern1 / 6,062 | 0.00016 |
| South Asian35 / 30,544 | 0.0011 |
This variant is present in gnomAD v4.1 (AF= 6.31984e-05; MAF= 0.00632%, 102/1613966 alleles, homozygotes = 0) and has highest observed frequency in the South Asian population (AF= 0.00110906; MAF= 0.11091%, 101/91068 alleles, homozygotes = 0); grpmax FAF= 0.00093302.
This variant is present in gnomAD v2.1 (AF= 0.000141436; MAF= 0.01414%, 35/247462 alleles, homozygotes = 0) and has highest observed frequency in the South Asian population (AF= 0.00114589; MAF= 0.11459%, 35/30544 alleles, homozygotes = 0); grpmax FAF= 0.00084634.
Not available in gnomAD-Canada v1.0.
No further detail was recorded.
SpliceAI predicts no significant splice impact for this variant (max delta score = 0.04). BayesDel score = 0.566539.
7 paper records listed. 1 cited in the classification.
c.C58T p.Q20X SQ/TQ 1 Baloch et al. [43].
Location Table 1 (mutation list), Table 3 (Case 9193 clinical details), Results para 3, Discussion
Screenshots represent source records captured during evidence collection. Select one to view the recorded source content.
The evidence statements recorded by the interpretation pipeline. They have not been reinterpreted by the page.
This variant is present in gnomAD v4.1 (AF= 6.31984e-05; MAF= 0.00632%, 102/1613966 alleles, homozygotes = 0) and has highest observed frequency in the South Asian population (AF= 0.00110906; MAF= 0.11091%, 101/91068 alleles, homozygotes = 0); grpmax FAF= 0.00093302.
This variant is present in gnomAD v2.1 (AF= 0.000141436; MAF= 0.01414%, 35/247462 alleles, homozygotes = 0) and has highest observed frequency in the South Asian population (AF= 0.00114589; MAF= 0.11459%, 35/30544 alleles, homozygotes = 0); grpmax FAF= 0.00084634.
Not available in gnomAD-Canada v1.0.
This variant has been reported in ClinVar as Pathogenic (15 clinical laboratories) and as Likely pathogenic (3 clinical laboratories) and as Uncertain significance (1 clinical laboratory) and as Likely Pathogenic (1 clinical laboratory) and as pathogenic (1 clinical laboratory). (ClinVarID = 133887)
SpliceAI predicts no significant splice impact for this variant (max delta score = 0.04). BayesDel score = 0.566539.
OncoKB identified variant-specific curated literature and context relevant to functional review; biological-effect context: Likely Loss-of-function; curated oncogenicity label: Likely Oncogenic.
This variant does not lie in a statistically significant hotspot. This variant has not previously been reported in somatic cancers (COSMIC).
This variant does not lie in a statistically significant hotspot.