Is ABCB4 p.Gln423Pro (c.1268A>C) pathogenic?

ABCB4 p.Gln423Pro (c.1268A>C) is classified Uncertain significance in ABCB4 (ClinVar, Single submitter, 1 submitter; last evaluated 2026-04-14). AlphaMissense: likely pathogenic (0.863); Very rare (popmax 0.00133%, afr); Associated with gallbladder disease 1.

What condition is associated with ABCB4 p.Gln423Pro (c.1268A>C)?

ABCB4 p.Gln423Pro (c.1268A>C) is associated with gallbladder disease 1 (ClinVar).

How common is ABCB4 p.Gln423Pro (c.1268A>C) in the general population?

ABCB4 p.Gln423Pro (c.1268A>C) is very rare (popmax 0.00133%, afr) (gnomAD).

How is Low phospholipid-associated cholelithiasis inherited?

Typically Autosomal dominant, Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

What do computational predictors say about ABCB4 p.Gln423Pro (c.1268A>C)?

AlphaMissense predicts likely pathogenic (score 0.863) — an in-silico prediction, not a clinical call.

ABCB4 p.Gln423Pro

c.1268A>C · VCV4846584

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.863 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.00133%, afr)

Missense predictors

3/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

gallbladder disease 1

Computational evidence

Protein change
AlphaMissense	0.863	likely pathogenic
REVEL	0.867	moderately pathogenic-leaning
SaProt	LLR -15.72	damaging
⇒ AlphaMissense, REVEL and SaProt all call this damaging.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 3.5	GERP 1.9, phastCons 1
Regional constraint	o/e 0.74	unconstrained · MANE · 31 kb · p 4.4e-11 · regional, not allelic
Overall
CADD	25.1	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 0.00133% African / African-American · 1/74,914 alleles

Overall 0.000657% 1/152,152 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: ABCB4
Protein: p.Gln423Pro
Coding: c.1268A>C
MANE Select: NM_000443
Type: single nucleotide variant
Location: chr7:87443407 (GRCh38)
Gene constraint: LOEUF 0.623 · pLI <0.01 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 83.36 · 4 PDB
Residue 423: the abc transporter 1 domain

Full ABCB4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

gallbladder disease 1 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Low phospholipid-associated cholelithiasis (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive
Onset: Adult

Similar variants

ABCB4 p.Gln423_Thr424insLys Uncertain significance ★ same residue
ABCB4 p.Gln423Lys Uncertain significance ★ ⚠ same residue
ABCB4 c.1356+2T>C Pathogenic/Likely pathogenic ★★ same condition
ABCB4 c.2211+1G>A Pathogenic/Likely pathogenic ★★ same condition
ABCB4 c.2682+1G>A Pathogenic/Likely pathogenic ★★ same condition
ABCB4 c.286+1G>A Pathogenic ★★ same condition
ABCB4 c.3486+1G>A Pathogenic/Likely pathogenic ★★ same condition
ABCB4 c.3486+5G>A Likely 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/abcb4-p-gln423pro (accessed [today's date]).

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