Is EP300 p.Asn660Ser (c.1979A>G) pathogenic?

EP300 p.Asn660Ser (c.1979A>G) is classified Uncertain significance in EP300 (ClinVar, Single submitter, 1 submitter; last evaluated 2026-01-22). AlphaMissense: likely benign (0.0538); Absent from gnomAD v4.1; Associated with Rubinstein-Taybi syndrome due to EP300 haploinsufficiency.

What condition is associated with EP300 p.Asn660Ser (c.1979A>G)?

EP300 p.Asn660Ser (c.1979A>G) is associated with Rubinstein-Taybi syndrome due to EP300 haploinsufficiency (ClinVar).

How common is EP300 p.Asn660Ser (c.1979A>G) in the general population?

EP300 p.Asn660Ser (c.1979A>G) is absent from gnomAD v4.1 (gnomAD).

What do computational predictors say about EP300 p.Asn660Ser (c.1979A>G)?

AlphaMissense predicts likely benign (score 0.0538) — an in-silico prediction, not a clinical call.

EP300 p.Asn660Ser

c.1979A>G · VCV4854503

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0538 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

Rubinstein-Taybi syndrome due to EP300 haploinsufficiency

Computational evidence

Protein change
AlphaMissense	0.0538	likely benign
REVEL	0.158	moderately benign-leaning
SaProt	LLR -6.45	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 2.4	GERP -1.1, phastCons 1
Regional constraint	o/e 1.10	unconstrained · MANE · 11 kb · p 0.024 · regional, not allelic
Overall
CADD	15.24	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: EP300
Protein: p.Asn660Ser
Coding: c.1979A>G
MANE Select: NM_001429
Type: single nucleotide variant
Location: chr22:41141148 (GRCh38)
Gene constraint: LOEUF 0.164 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 54.88 · 60 PDB

Full EP300 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Rubinstein-Taybi syndrome due to EP300 haploinsufficiency — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

EP300 c.1282+1G>A Pathogenic/Likely pathogenic ★★ same condition
EP300 c.3671+1G>A Pathogenic/Likely pathogenic ★★ same condition
EP300 c.3729-2A>G Pathogenic/Likely pathogenic ★★ same condition
EP300 c.3857A>G Pathogenic/Likely pathogenic ★★ ⚠ same condition
EP300 p.Arg1055Ter Pathogenic ★★ same condition
EP300 p.Arg1312Ter Pathogenic ★★ same condition
EP300 p.Arg1356Ter Pathogenic ★★ same condition
EP300 p.Arg1462Ter 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/ep300-p-asn660ser (accessed [today's date]).

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