Is AP3D1 p.Arg556Trp (c.1666C>T) pathogenic?

AP3D1 p.Arg556Trp (c.1666C>T) is classified Uncertain significance in AP3D1 (ClinVar, Single submitter, 1 submitter; last evaluated 2022-12-18). AlphaMissense: likely benign (0.1749); Very rare (popmax 0.00267%, afr).

How common is AP3D1 p.Arg556Trp (c.1666C>T) in the general population?

AP3D1 p.Arg556Trp (c.1666C>T) is very rare (popmax 0.00267%, afr) (gnomAD).

What do computational predictors say about AP3D1 p.Arg556Trp (c.1666C>T)?

AlphaMissense predicts likely benign (score 0.1749) — an in-silico prediction, not a clinical call.

AP3D1 p.Arg556Trp

c.1666C>T · rs755474562 · VCV1440643

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.1749 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00267%, afr)

Missense predictors

1/2 damaging

AlphaMissense, SaProt · REVEL no call

Computational evidence

Protein change
AlphaMissense	0.1749	likely benign
REVEL	0.3	indeterminate
SaProt	LLR -11.65	damaging
⇒ SaProt calls this damaging; AlphaMissense does not; REVEL makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 7.3	GERP 0.028, phastCons 1
Regional constraint	o/e 0.80	unconstrained · MANE · 4,612 bp · p 7.4e-05 · regional, not allelic
Overall
CADD	29.1	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 0.00267% African / African-American · 2/74,930 alleles

Filtering AF 0.0013% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00108%

Overall 0.00167% 27/1,612,352 alleles · very rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00267%	37,465
East Asian	0.00223%	44,900
European (non-Finnish)	0.00195%	51,305
Finnishnot grpmax-eligible	0.0016%	62,336

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: AP3D1
Protein: p.Arg556Trp
Coding: c.1666C>T
MANE Select: NM_001261826
dbSNP: rs755474562
Type: single nucleotide variant
Location: chr19:2118648 (GRCh38)
Gene constraint: LOEUF 0.443 · pLI 1.00 (gnomAD)
Structure: AlphaFold pLDDT 76.45 · 6 PDB

Full AP3D1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

AP3D1 p.Arg556Gln Uncertain significance ★★ ⚠ same residue
AP3D1 p.Arg556Gly Uncertain significance ★★ ⚠ same residue
AP3D1 c.2001+6C>T Uncertain significance ★★ same type
AP3D1 c.2601+6G>T Uncertain significance ★★ same type
AP3D1 c.856+3G>A Uncertain significance ★★ same type
AP3D1 p.Ala1076Val Uncertain significance ★★ ⚠ same type
AP3D1 p.Ala1093Val Uncertain significance ★★ ⚠ same type
AP3D1 p.Ala1148Val 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/ap3d1-p-arg556trp (accessed [today's date]).

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