Is CDC20 p.Arg322Ter (c.964C>T) pathogenic?

CDC20 p.Arg322Ter (c.964C>T) is classified Pathogenic in CDC20 (ClinVar, No assertion criteria, 1 submitter; last evaluated 2023-04-10). Very rare (popmax 0.00667%, afr); Associated with oocyte maturation defect 14.

What condition is associated with CDC20 p.Arg322Ter (c.964C>T)?

CDC20 p.Arg322Ter (c.964C>T) is associated with oocyte maturation defect 14 (ClinVar).

How common is CDC20 p.Arg322Ter (c.964C>T) in the general population?

CDC20 p.Arg322Ter (c.964C>T) is very rare (popmax 0.00667%, afr) (gnomAD).

CDC20 p.Arg322Ter

c.964C>T · rs372597302 · VCV2443923

Pathogenic No assertion criteria

Classification

Pathogenic

ClinVar

Review

No assertion criteria ☆☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.00667%, afr)

Conditions

oocyte maturation defect 14

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function
NMD	predicted	premature termination codon in exon 8 of 11
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 6	GERP 0.012, phastCons 1
Overall
CADD	38.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00667% African / African-American · 5/74,910 alleles

Filtering AF 0.00255% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00161%

Overall 0.00192% 31/1,613,928 alleles · very rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00667%	14,982
Remaining individualsnot grpmax-eligible	0.0048%	20,826
East Asian	0.00223%	44,888
European (non-Finnish)	0.00178%	56,187
South Asian	0.0011%	91,080

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: CDC20
Protein: p.Arg322Ter
Coding: c.964C>T
MANE Select: NM_001255
dbSNP: rs372597302
Type: single nucleotide variant
Location: chr1:43360848 (GRCh38)
Gene constraint: LOEUF 0.744 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 84.39 · 17 PDB
Residue 322: a UniProt-annotated variant site (in ozema14; severely decreased function in metaphase/anaphase transition of meiosis i; does not fully rescue metaphase i arrest in cdc20-knocked down mouse oocytes; decreased function in positive regulation of anaphase-promoting complex-dependent catabolic process; fails to localize to the kinetochore); a UniProt-annotated variant site (in ozema14); a UniProt-annotated variant site (in ozema14; severely decreased function in metaphase/anaphase transition of meiosis i; does not fully rescue metaphase i arrest in cdc20-knocked down mouse oocytes; decreased function in positive regulation of anaphase-promoting complex-dependent catabolic process; shows normal kinetochore localization); a β-strand

Full CDC20 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

oocyte maturation defect 14 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

CDC20 p.Arg322Gln Pathogenic ⚠ same residue
CDC20 p.Cys364Ter Likely pathogenic ★ same condition
CDC20 c.556+1G>T Conflicting classifications of pathogenicity ★ same condition
CDC20 c.330+1G>A Pathogenic same condition
CDC20 p.Ala211Thr Pathogenic ⚠ same condition
CDC20 p.Arg182Ter Pathogenic same condition
CDC20 p.Arg262Ter Pathogenic same condition
CDC20 p.Trp385Cys Pathogenic same condition

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/cdc20-p-arg322ter (accessed [today's date]).

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