Is CCDC8 p.Ala166Ser (c.496G>T) pathogenic?

CCDC8 p.Ala166Ser (c.496G>T) is classified Uncertain significance in CCDC8 (ClinVar, Single submitter, 1 submitter; last evaluated 2022-03-18). AlphaMissense: likely benign (0.0892); Absent from gnomAD v4.1.

How common is CCDC8 p.Ala166Ser (c.496G>T) in the general population?

CCDC8 p.Ala166Ser (c.496G>T) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about CCDC8 p.Ala166Ser (c.496G>T)?

AlphaMissense predicts likely benign (score 0.0892) — an in-silico prediction, not a clinical call.

CCDC8 p.Ala166Ser

c.496G>T · rs2147432542 · VCV1482164

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0892 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.0892	likely benign
REVEL	0.046	moderately benign-leaning
SaProt	LLR -6.30	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 0.28	GERP -0.68
Regional constraint	o/e 1.02	unconstrained · MANE · 1,613 bp · p 0.66 · regional, not allelic
Overall
CADD	18.49	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

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.Ala166Ser
Coding: c.496G>T
MANE Select: NM_032040
dbSNP: rs2147432542
Type: single nucleotide variant
Location: chr19:46412315 (GRCh38)
Gene constraint: LOEUF 1.796 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 46.83 · 1 PDB

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

Similar variants

CCDC8 p.Ala217Thr Uncertain significance ★★ ⚠ same type
CCDC8 p.Ala293Thr Uncertain significance ★★ ⚠ same type
CCDC8 p.Ala393Val Uncertain significance ★★ ⚠ same type
CCDC8 p.Ala527Val Uncertain significance ★★ ⚠ same type
CCDC8 p.Arg15Gln Uncertain significance ★★ ⚠ same type
CCDC8 p.Arg225Gly Uncertain significance ★★ ⚠ same type
CCDC8 p.Arg277His Uncertain significance ★★ ⚠ same type
CCDC8 p.Arg277Ser Uncertain significance ★★ ⚠ same type

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-ala166ser (accessed [today's date]).

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