Is CCDC8 p.Ser261Pro (c.781T>C) pathogenic?

CCDC8 p.Ser261Pro (c.781T>C) is classified Likely benign in CCDC8 (ClinVar, Single submitter, 1 submitter; last evaluated 2023-11-29). AlphaMissense: likely benign (0.0697); Absent from gnomAD v4.1; Associated with Inborn genetic diseases.

What condition is associated with CCDC8 p.Ser261Pro (c.781T>C)?

CCDC8 p.Ser261Pro (c.781T>C) is associated with Inborn genetic diseases (ClinVar).

How common is CCDC8 p.Ser261Pro (c.781T>C) in the general population?

CCDC8 p.Ser261Pro (c.781T>C) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about CCDC8 p.Ser261Pro (c.781T>C)?

AlphaMissense predicts likely benign (score 0.0697) — an in-silico prediction, not a clinical call.

CCDC8 p.Ser261Pro

c.781T>C · rs2513601831 · VCV3139414

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0697 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

Inborn genetic diseases

Computational evidence

Protein change
AlphaMissense	0.0697	likely benign
REVEL	0.009	strongly benign-leaning
SaProt	LLR -5.27	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 0.11	GERP -2.8
Regional constraint	o/e 1.02	unconstrained · MANE · 1,613 bp · p 0.66 · regional, not allelic
Overall
CADD	5.51	PHRED · no single calibrated threshold — expert panels disagree

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

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: CCDC8
Protein: p.Ser261Pro
Coding: c.781T>C
MANE Select: NM_032040
dbSNP: rs2513601831
Type: single nucleotide variant
Location: chr19:46412030 (GRCh38)
Gene constraint: LOEUF 1.796 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 46.83 · 1 PDB
Residue 261: a modified residue (phosphoserine); the 'disordered' region

Full CCDC8 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Inborn genetic diseases — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

CCDC8 p.Ser261Tyr Benign/Likely benign ★★ ⚠ same residue
CCDC8 p.Ala217Thr Uncertain significance ★★ ⚠ same condition
CCDC8 p.Ala293Thr Uncertain significance ★★ ⚠ same condition
CCDC8 p.Ala393Val Uncertain significance ★★ ⚠ same condition
CCDC8 p.Ala527Val Uncertain significance ★★ ⚠ same condition
CCDC8 p.Arg15Gln Uncertain significance ★★ ⚠ same condition
CCDC8 p.Arg225Gly Uncertain significance ★★ ⚠ same condition
CCDC8 p.Arg277His Uncertain significance ★★ ⚠ 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/ccdc8-p-ser261pro (accessed [today's date]).

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