Is AP1B1 p.Pro125Arg (c.374C>G) pathogenic?

AP1B1 p.Pro125Arg (c.374C>G) is classified Uncertain significance in AP1B1 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-05-28). AlphaMissense: likely pathogenic (0.9996); Very rare (popmax 0.000169%, nfe); Associated with Inborn genetic diseases.

What condition is associated with AP1B1 p.Pro125Arg (c.374C>G)?

AP1B1 p.Pro125Arg (c.374C>G) is associated with Inborn genetic diseases (ClinVar).

How common is AP1B1 p.Pro125Arg (c.374C>G) in the general population?

AP1B1 p.Pro125Arg (c.374C>G) is very rare (popmax 0.000169%, nfe) (gnomAD).

What do computational predictors say about AP1B1 p.Pro125Arg (c.374C>G)?

AlphaMissense predicts likely pathogenic (score 0.9996) — an in-silico prediction, not a clinical call.

AP1B1 p.Pro125Arg

c.374C>G · VCV3922004

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.9996 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.000169%, nfe)

Missense predictors

2/2 damaging

AlphaMissense, SaProt · REVEL no call

Conditions

Inborn genetic diseases

Computational evidence

Protein change
AlphaMissense	0.9996	likely pathogenic · top 6% in AP1B1
REVEL	0.596	indeterminate
SaProt	LLR -19.03	damaging
⇒ AlphaMissense and SaProt both call this damaging; REVEL makes no call.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 12	GERP 2, phastCons 1
Regional constraint	o/e 0.68	unconstrained · MANE · 18 kb · p 1.2e-17 · regional, not allelic
Overall
CADD	32.0	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean damaging — 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 0.000169% European (non-Finnish) · 2/1,179,984 alleles

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

Overall 0.000124% 2/1,613,918 alleles · very rare

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: AP1B1
Protein: p.Pro125Arg
Coding: c.374C>G
MANE Select: NM_001127
Type: single nucleotide variant
Location: chr22:29358877 (GRCh38)
Gene constraint: LOEUF 0.476 · pLI 0.99 (gnomAD)
Structure: AlphaFold pLDDT 82.46 · 20 PDB
Residue 125: an α-helix

Full AP1B1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

Inborn genetic diseases — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

AP1B1 p.Asp234Asn Uncertain significance ★★ ⚠ same condition
AP1B1 p.Gly568Ser Uncertain significance ★★ ⚠ same condition
AP1B1 c.2310-3C>G Uncertain significance ★ same condition
AP1B1 p.Ala254Thr Uncertain significance ★ ⚠ same condition
AP1B1 p.Ala352Thr Uncertain significance ★ ⚠ same condition
AP1B1 p.Ala410Thr Uncertain significance ★ ⚠ same condition
AP1B1 p.Ala598Val Uncertain significance ★ ⚠ same condition
AP1B1 p.Ala689Pro 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/ap1b1-p-pro125arg (accessed [today's date]).

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