Is EP300 p.Ala1787= (c.5361C>T) pathogenic?

EP300 p.Ala1787= (c.5361C>T) is classified Likely benign in EP300 (ClinVar, Multiple submitters, 3 submitters; last evaluated 2025-01-08). Ultra-rare (popmax 0.0135%, nfe); Associated with Rubinstein-Taybi syndrome due to EP300 haploinsufficiency.

What condition is associated with EP300 p.Ala1787= (c.5361C>T)?

EP300 p.Ala1787= (c.5361C>T) is associated with Rubinstein-Taybi syndrome due to EP300 haploinsufficiency (ClinVar).

How common is EP300 p.Ala1787= (c.5361C>T) in the general population?

EP300 p.Ala1787= (c.5361C>T) is ultra-rare (popmax 0.0135%, nfe) (gnomAD).

EP300 p.Ala1787=

c.5361C>T · rs200552141 · VCV772365

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0135%, nfe)

Conditions

Rubinstein-Taybi syndrome due to EP300 haploinsufficiency

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -0.88	GERP -0.78, phastCons 0.002
Overall
CADD	9.53	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0135% European (non-Finnish) · 159/1,180,036 alleles

Filtering AF 0.0117% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0111%

Overall 0.0106% 171/1,614,014 alleles · ultra-rare

Ancestry group	Frequency	1 in
European (non-Finnish)grpmax	0.0135%	7,422
Remaining individualsnot grpmax-eligible	0.0096%	10,414
Finnishnot grpmax-eligible	0.00469%	21,339
Admixed American	0.00333%	30,001
African / African-American	0.00134%	74,894

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: EP300
Protein: p.Ala1787=
Coding: c.5361C>T
MANE Select: NM_001429
dbSNP: rs200552141
Type: single nucleotide variant
Location: chr22:41177072 (GRCh38)
Gene constraint: LOEUF 0.164 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 54.88 · 60 PDB
Residue 1787: the 'binding region for e1a adenovirus' region; an α-helix

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-ala1787 (accessed [today's date]).

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