Is CHEK2 p.Cys124= (c.372C>T) pathogenic?

CHEK2 p.Cys124= (c.372C>T) is classified Benign/Likely benign in CHEK2 (ClinVar, Multiple submitters, 3 submitters; last evaluated 2025-11-09). Absent from gnomAD v4.1; Associated with hereditary neoplastic syndrome.

What condition is associated with CHEK2 p.Cys124= (c.372C>T)?

CHEK2 p.Cys124= (c.372C>T) is associated with hereditary neoplastic syndrome, hereditary breast carcinoma (ClinVar).

How common is CHEK2 p.Cys124= (c.372C>T) in the general population?

CHEK2 p.Cys124= (c.372C>T) is absent from gnomAD v4.1 (gnomAD).

CHEK2 p.Cys124=

c.372C>T · rs1555927291 · VCV1734371

Benign/Likely benign Multiple submitters

Classification

Benign/Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

gnomAD v4.1

Absent

absent from gnomAD v4.1

Conditions

hereditary neoplastic syndrome

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 3.9	GERP -0.13, phastCons 1
Overall
CADD	10.31	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Absent from gnomAD v4.1. Not observed in any sequenced alleles — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

Variant & gene context

Gene: CHEK2
Protein: p.Cys124=
Coding: c.372C>T
MANE Select: NM_007194
dbSNP: rs1555927291
Type: single nucleotide variant
Location: chr22:28725315 (GRCh38)
Gene constraint: LOEUF 1.399 · pLI <0.01 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 77.64 · 38 PDB
Residue 124: the fha domain; a β-strand

Full CHEK2 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

hereditary neoplastic syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: hereditary breast carcinoma

Similar variants

CHEK2 p.Cys124Phe Uncertain significance ★★ same residue
CHEK2 p.Cys124Tyr Uncertain significance ★★ ⚠ same residue
CHEK2 p.Cys124Arg Uncertain significance ★ same residue
CHEK2 p.Cys124Ser Uncertain significance ★ ⚠ same residue
CHEK2 p.Cys124Trp Uncertain significance ★ ⚠ same residue
CHEK2 p.Cys124fs Pathogenic ★★ same residue
CHEK2 p.Cys124Ter Likely pathogenic ★ same residue
CDS1 p.His124Asn Uncertain significance ★ ⚠ same residue

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/chek2-p-cys124 (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown