Is APOB p.His48Leu (c.143A>T) pathogenic?

APOB p.His48Leu (c.143A>T) is classified Uncertain significance in APOB (ClinVar, Multiple submitters, 2 submitters; last evaluated 2022-06-15). AlphaMissense: likely benign (0.1912); Very rare (popmax 8.47e-05%, nfe); Associated with familial hypobetalipoproteinemia 1.

What condition is associated with APOB p.His48Leu (c.143A>T)?

APOB p.His48Leu (c.143A>T) is associated with familial hypobetalipoproteinemia 1, familial hypercholesterolemia, hypercholesterolemia, autosomal dominant, type B (ClinVar).

How common is APOB p.His48Leu (c.143A>T) in the general population?

APOB p.His48Leu (c.143A>T) is very rare (popmax 8.47e-05%, nfe) (gnomAD).

What do computational predictors say about APOB p.His48Leu (c.143A>T)?

AlphaMissense predicts likely benign (score 0.1912) — an in-silico prediction, not a clinical call.

APOB p.His48Leu

c.143A>T · rs1415387096 · VCV919961

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

AlphaMissense

likely benign

0.1912 · ACMG-weighted

gnomAD v4.1

Rare

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

Missense predictors

0/2 damaging

AlphaMissense, REVEL

Conditions

familial hypobetalipoproteinemia 1

Computational evidence

Protein change
AlphaMissense	0.1912	likely benign
REVEL	0.125	moderately benign-leaning
⇒ AlphaMissense and REVEL both call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 1.2	GERP -0.91, phastCons 1
Regional constraint	o/e 1.00	unconstrained · MANE · 32 kb · p 0.91 · regional, not allelic
Overall
CADD	17.73	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 8.47e-05% European (non-Finnish) · 1/1,180,020 alleles

Overall 0.000137% 2/1,461,874 alleles · very rare

Ancestry group	Frequency	1 in
Remaining individualsnot grpmax-eligible	0.0016%	62,508
European (non-Finnish)grpmax	8.47e-05%	1,180,020

Remaining individuals 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: APOB
Protein: p.His48Leu
Coding: c.143A>T
MANE Select: NM_000384
dbSNP: rs1415387096
Type: single nucleotide variant
Location: chr2:21042455 (GRCh38)
Gene constraint: LOEUF 0.537 · pLI <0.01 · ClinGen HI 3/3 (gnomAD)
Residue 48: the vitellogenin domain; a disulfide bond; the 'heparin-binding' region

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

Disease context

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

Also linked: familial hypercholesterolemia hypercholesterolemia, autosomal dominant, type B

Similar variants

APOB p.His48Gln Uncertain significance ★ ⚠ same residue
APOB p.His48= Likely benign ★ same residue
APOB c.1830-1G>A Pathogenic ★★ same condition
APOB c.2604+1G>A Likely pathogenic ★★ same condition
APOB c.537+1G>T Pathogenic/Likely pathogenic ★★ same condition
APOB p.Arg1333Ter Pathogenic ★★ same condition
APOB p.Arg2012Ter Pathogenic ★★ same condition
APOB p.Arg2085Ter 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/apob-p-his48leu (accessed [today's date]).

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