Is CCT8 p.Phe22Leu (c.64T>C) pathogenic?

CCT8 p.Phe22Leu (c.64T>C) is classified Uncertain significance in CCT8 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-04-20). AlphaMissense: likely pathogenic (0.9621); Very rare (popmax 0.00403%, afr).

How common is CCT8 p.Phe22Leu (c.64T>C) in the general population?

CCT8 p.Phe22Leu (c.64T>C) is very rare (popmax 0.00403%, afr) (gnomAD).

What do computational predictors say about CCT8 p.Phe22Leu (c.64T>C)?

AlphaMissense predicts likely pathogenic (score 0.9621) — an in-silico prediction, not a clinical call.

CCT8 p.Phe22Leu

c.64T>C · VCV3997898

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.9621 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00403%, afr)

Missense predictors

1/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.9621	likely pathogenic
REVEL	0.189	benign-leaning
SaProt	LLR -8.28	tolerated
⇒ AlphaMissense calls this damaging; REVEL and SaProt do not.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 11	GERP 1.7, phastCons 1
Regional constraint	o/e 0.85	unconstrained · MANE · 17 kb · p 9.2e-05 · regional, not allelic
Overall
CADD	22.4	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

Grpmax group 0.00403% African / African-American · 3/74,476 alleles

Filtering AF 0.00107% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000497%

Overall 0.000207% 3/1,450,728 alleles · very rare

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: CCT8
Protein: p.Phe22Leu
Coding: c.64T>C
MANE Select: NM_006585
Type: single nucleotide variant
Location: chr21:29070334 (GRCh38)
Gene constraint: LOEUF 0.287 · pLI 1.00 (gnomAD)
Structure: AlphaFold pLDDT 87.85 · 71 PDB
Residue 22: a β-strand

Full CCT8 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

CCT8 p.Val409Ile Benign ★★ same type
CCT8 p.Ala12Thr Uncertain significance ★ ⚠ same type
CCT8 p.Ala186Thr Uncertain significance ★ ⚠ same type
CCT8 p.Ala298Thr Uncertain significance ★ ⚠ same type
CCT8 p.Ala35Thr Uncertain significance ★ ⚠ same type
CCT8 p.Ala442Gly Uncertain significance ★ ⚠ same type
CCT8 p.Ala447Val Uncertain significance ★ ⚠ same type
CCT8 p.Ala451Thr 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/cct8-p-phe22leu (accessed [today's date]).

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