Is APBA3 p.Pro136Ala (c.406C>G) pathogenic?

APBA3 p.Pro136Ala (c.406C>G) is classified Uncertain significance in APBA3 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-04-17). AlphaMissense: likely benign (0.0749); Ultra-rare (popmax 0.0317%, amr).

How common is APBA3 p.Pro136Ala (c.406C>G) in the general population?

APBA3 p.Pro136Ala (c.406C>G) is ultra-rare (popmax 0.0317%, amr) (gnomAD).

What do computational predictors say about APBA3 p.Pro136Ala (c.406C>G)?

AlphaMissense predicts likely benign (score 0.0749) — an in-silico prediction, not a clinical call.

APBA3 p.Pro136Ala

c.406C>G · VCV3924463

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0749 · ACMG-weighted

gnomAD v4.1

Rare

ultra-rare (popmax 0.0317%, amr)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Computational evidence

Protein change
AlphaMissense	0.0749	likely benign
REVEL	0.037	moderately benign-leaning
SaProt	LLR -6.63	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	<0.2	no splice effect predicted · four deltas, not one · how we know
Constraint at this position
Conservation	phyloP 9.4	GERP 0.41, phastCons 1
Regional constraint	o/e 1.05	unconstrained · MANE · 9,235 bp · p 0.12 · regional, not allelic
Overall
CADD	16.44	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 0.0317% Admixed American · 19/59,886 alleles

Filtering AF 0.0207% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0172%

Overall 0.0013% 21/1,612,558 alleles · ultra-rare exomes 17/1,460,384 · genomes 4/152,174 · joint denominator

Ancestry group	Frequency	1 in
Admixed Americangrpmax	0.0317%	3,152
Remaining individualsnot grpmax-eligible	0.0016%	62,448
European (non-Finnish)	8.48e-05%	1,179,871

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: APBA3
Protein: p.Pro136Ala
Coding: c.406C>G
MANE Select: NM_004886
Type: single nucleotide variant
Location: chr19:3759859 (GRCh38)
Gene constraint: LOEUF 1.237 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 64.79 · 3 PDB
Residue 136: the 'disordered' region

Full APBA3 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Similar variants

APBA3 p.Pro136Arg Uncertain significance ★ ⚠ same residue
APBA3 p.Ala158Val Uncertain significance ★ ⚠ same type
APBA3 p.Ala202Val Uncertain significance ★ ⚠ same type
APBA3 p.Ala223Val Uncertain significance ★ ⚠ same type
APBA3 p.Ala308Val Uncertain significance ★ ⚠ same type
APBA3 p.Ala317Val Uncertain significance ★ ⚠ same type
APBA3 p.Ala335Thr Uncertain significance ★ ⚠ same type
APBA3 p.Ala335Val 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/apba3-p-pro136ala (accessed [today's date]).

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