Is CCNO p.Ser330Phe (c.989C>T) pathogenic?

CCNO p.Ser330Phe (c.989C>T) is classified Uncertain significance in CCNO (ClinVar, Single submitter, 1 submitter; last evaluated 2022-09-01). AlphaMissense: likely benign (0.2629); Very rare (popmax 0.00167%, amr); Associated with primary ciliary dyskinesia.

What condition is associated with CCNO p.Ser330Phe (c.989C>T)?

CCNO p.Ser330Phe (c.989C>T) is associated with primary ciliary dyskinesia (ClinVar).

How common is CCNO p.Ser330Phe (c.989C>T) in the general population?

CCNO p.Ser330Phe (c.989C>T) is very rare (popmax 0.00167%, amr) (gnomAD).

How is Primary ciliary dyskinesia inherited?

Typically Autosomal dominant, Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about CCNO p.Ser330Phe (c.989C>T)?

AlphaMissense predicts likely benign (score 0.2629) — an in-silico prediction, not a clinical call.

CCNO p.Ser330Phe

c.989C>T · rs750696117 · VCV454921

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.2629 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00167%, amr)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

primary ciliary dyskinesia

Computational evidence

Protein change
AlphaMissense	0.2629	likely benign
REVEL	0.173	moderately benign-leaning
SaProt	LLR -5.40	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 12	GERP 1.9, phastCons 1
Regional constraint	o/e 1.14	unconstrained · MANE · 2,145 bp · p 0.0026 · regional, not allelic
Overall
CADD	25.8	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

Grpmax group 0.00167% Admixed American · 1/60,014 alleles

Filtering AF 2.8e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 1.1e-05%

Overall 0.000372% 6/1,614,048 alleles · very rare

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.00167%	60,014
Remaining individualsnot grpmax-eligible	0.0016%	62,488
Finnishnot grpmax-eligible	0.00156%	63,996
African / African-American	0.00133%	74,944
European (non-Finnish)	0.000169%	590,012

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: CCNO
Protein: p.Ser330Phe
Coding: c.989C>T
MANE Select: NM_021147
dbSNP: rs750696117
Type: single nucleotide variant
Location: chr5:55231439 (GRCh38)
Gene constraint: LOEUF 1.698 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 79.06

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

Disease context

primary ciliary dyskinesia — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Primary ciliary dyskinesia (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive, X-linked recessive
Onset: Neonatal
Prevalence: 1-5 / 10 000 (Pakistan)

Similar variants

CCNO p.Gln103Ter Pathogenic ★★ same condition
CCNO p.Ala14Ser Uncertain significance ★★ ⚠ same condition
CCNO p.Ala202Val Uncertain significance ★★ ⚠ same condition
CCNO p.Ala230Thr Uncertain significance ★★ ⚠ same condition
CCNO p.Ala258Gly Uncertain significance ★★ ⚠ same condition
CCNO p.Arg124Leu Uncertain significance ★★ ⚠ same condition
CCNO p.Arg124Trp Uncertain significance ★★ ⚠ same condition
CCNO p.Arg133Leu 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/ccno-p-ser330phe (accessed [today's date]).

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