Is ABCB4 p.Gln440Ter (c.1318C>T) pathogenic?

ABCB4 p.Gln440Ter (c.1318C>T) is classified Pathogenic/Likely pathogenic in ABCB4 (ClinVar, Multiple submitters, 3 submitters; last evaluated 2025-08-14). Very rare (popmax 8.47e-05%, nfe); Associated with gallbladder disease 1.

What condition is associated with ABCB4 p.Gln440Ter (c.1318C>T)?

ABCB4 p.Gln440Ter (c.1318C>T) is associated with gallbladder disease 1 (ClinVar).

How common is ABCB4 p.Gln440Ter (c.1318C>T) in the general population?

ABCB4 p.Gln440Ter (c.1318C>T) is very rare (popmax 8.47e-05%, nfe) (gnomAD).

How is Low phospholipid-associated cholelithiasis inherited?

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

ABCB4 p.Gln440Ter

c.1318C>T · rs1265221541 · VCV2805923

Pathogenic/Likely pathogenic Multiple submitters

Classification

Pathogenic/Likely pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 8.47e-05%, nfe)

Conditions

gallbladder disease 1

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function in a haploinsufficient gene (ClinGen)
NMD	predicted	premature termination codon in exon 12 of 28
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 12	GERP 1.9, phastCons 1
Overall
CADD	40.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 8.47e-05% European (non-Finnish) · 1/1,180,008 alleles

Overall 0.000205% 3/1,461,846 alleles · very rare

Ancestry group	Frequency	1 in
Finnishnot grpmax-eligible	0.00312%	32,007
European (non-Finnish)grpmax	8.47e-05%	1,180,008

Finnish shows a higher raw frequency than the grpmax group above it. gnomAD excludes bottlenecked groups — Finnish, Ashkenazi Jewish, Amish and “Remaining individuals” — from grpmax, because founder effects make their frequencies unrepresentative for filtering. The table is sorted by frequency, so an excluded group can sit above the grpmax row.

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.Gln440Ter
Coding: c.1318C>T
MANE Select: NM_000443
dbSNP: rs1265221541
Type: single nucleotide variant
Location: chr7:87443357 (GRCh38)
Gene constraint: LOEUF 0.623 · pLI <0.01 · ClinGen HI 3/3 (gnomAD)
Structure: AlphaFold pLDDT 83.36 · 4 PDB
Residue 440: an α-helix; 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 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
ABCB4 c.80+1G>A Likely pathogenic ★★ same condition
ABCB4 c.834-1G>A Pathogenic/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-gln440ter (accessed [today's date]).

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