APP

Chr 21AD

amyloid beta precursor protein

Also known as: AAA, ABETA, ABPP, AD1, APPI, CTFgamma, CVAP, PN-II

The APP protein functions as a cell surface receptor involved in neurite growth, neuronal adhesion, axonogenesis, and synaptic formation, and is cleaved by secretases to produce peptides including those that form amyloid plaques. Mutations cause autosomal dominant familial Alzheimer disease and cerebral amyloid angiopathy with various geographic variants (Dutch, Italian, Iowa, Flemish, Arctic). The gene is highly constrained against loss-of-function variants (LOEUF 0.419), reflecting its essential neuronal functions.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt
MultiplemechanismADLOEUF 0.422 OMIM phenotypes
Clinical SummaryAPP
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Gene-Disease Validity (ClinGen)
cerebral amyloid angiopathy, APP-related · ADDefinitive

Definitive — sufficient evidence for diagnostic panels

Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.26) despite low pLI — interpret in context.
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ClinVar Variants
5 unique Pathogenic / Likely Pathogenic· 52 VUS of 100 total submissions
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Clinical Trials
12 active or recruiting trials — potential therapeutic options may be available
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GeneReview available — APP
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Moderate LoF intolerance
LoF Constraint
0.42LOEUF
pLI 0.047
Z-score 4.68
OE 0.26 (0.170.42)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint
1.39Z-score
OE missense 0.82 (0.750.89)
369 obs / 452.4 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.26 (0.170.42)
00.351.4
Missense OE0.82 (0.750.89)
00.61.4
Synonymous OE1.07
01.21.6
LoF obs/exp: 12 / 46.4Missense obs/exp: 369 / 452.4Syn Z: -0.70
DN
0.78top 25%
GOF
0.6930th %ile
LOF
0.3843th %ile

This gene has evidence for multiple mechanisms of pathogenicity (dominant-negative and gain-of-function). Both the Badonyi & Marsh prediction and the broader genomic evidence point to dominant-negative as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

DNprediction above median · 1 literature citation
GOFprediction above median · 1 literature citation

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Literature Evidence

DNMutations at or near binding sites not only reduced both the surface fraction of APP and membrane cholesterol levels in a dominant negative manner, but also increased synaptic vulnerability to moderate membrane cholesterol reduction.PMID:30885793
GOFWe demonstrate that pathological PS1 loss-of-function impinges on neurite formation through a selective APP gain-of-function that could impact on axodendritic connectivity and contribute to aberrant axonal sprouting observed in AD patients.PMID:27196744

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

100 submitted variants in ClinVar

Classification Summary

Pathogenic4
Likely Pathogenic1
VUS52
Likely Benign25
4
Pathogenic
1
Likely Pathogenic
52
VUS
25
Likely Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
4
0
4
Likely Pathogenic
0
0
1
0
1
VUS
1
42
6
3
52
Likely Benign
0
1
12
12
25
Benign
0
0
0
0
0
Total143231582

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

APP · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

Pregnancy RelatedPregnancy ComplicationsPregnancy, High Risk

Resources, Inspiration, Support and Empowerment (RISE) for Black Pregnant Women

ACTIVE NOT RECRUITING
NCT05552053Phase PHASE2, PHASE3Cedars-Sinai Medical CenterStarted 2023-06-01
MWSH plus Candlelit CareMWSH
Breast CancerDepression

E-Mindfulness Approaches for Living After Breast Cancer

RECRUITING
NCT06748222Phase PHASE3NRG OncologyStarted 2025-06-27
Mindfulness (MAPs) Live OnlineMindfulness (MAPs) Digital AppMeditation Only Control Group
MCIAlzheimer DiseaseVAD - Vascular Dementia

Cognitive Impairment in Ageing People

RECRUITING
NCT04360200Yamei TangStarted 2020-04-01
Alzheimer's Disease

A Phase 2b/3 Clinical Study Evaluating T3D-959 in Mild-to-Moderate Alzheimer's Disease Subjects

NOT YET RECRUITING
NCT06964230Phase PHASE2, PHASE3T3D Therapeutics, Inc.Started 2026-10-26
T3D-959Placebo Comparator
Cerebral Amyloid Aβ Angiopathy

Phenotypic and Molecular Characterisation of Cerebral Amyloid Angiopathy

RECRUITING
NCT06864000University Hospital, RouenStarted 2023-03-31
Cerebral Amyloid Angiopathy

SEarchiNg biomarkErs Cerebral Amyloid Angiopathy (SENECA)

RECRUITING
NCT04204642Fondazione I.R.C.C.S. Istituto Neurologico Carlo BestaStarted 2020-06-01
CAA patients data collection
Type 2 Diabetes

A Feasibility Study of Optimal Non-Pharmacological Lifestyle Modifications in People With Type 2 Diabetes

RECRUITING
NCT07262788Phase NASteno Diabetes Center CopenhagenStarted 2025-09-30
CH-rich diet with exerciseCH-reduced diet with exercise
DementiaCognitive DeclineAlzheimer Disease

Investigating Neurocognitive Disorders Epidemiology

RECRUITING
NCT06375213King Chulalongkorn Memorial HospitalStarted 2023-08-24
Plasma tau phosphorylated at Thr217Neurocognitive examination
Alzheimer DiseaseMild Cognitive Impairment Due to Alzheimer's Disease

Alzheimer's Disease Multinuclear Imaging Neuro-Enhanced Resolution (AD-MINER)

RECRUITING
NCT07089303Chinese PLA General HospitalStarted 2025-07-01
Parkinson DiseaseImpulse Control Disorder

Efficacy of a Prediction Model-based Algorithm to PREVENT Drug-induced Impulse Control Disorders in Parkinson's Disease

NOT YET RECRUITING
NCT07505394Phase NAAssistance Publique - Hôpitaux de ParisStarted 2026-06-01
Algorithm-guided groupStandard of Care (SoC) group
HomeostasisMetabolism and Nutrition DisorderHealthy

Energy Metabolism Profiles Over Weight-loss and Eating Responses

ACTIVE NOT RECRUITING
NCT05785221Phase NAChinese Academy of SciencesStarted 2023-03-02
General lifestyle and nutritional educationPersonalized nutritional and lifestyle weight reduction intervention
AmyloidosisAmyloid CardiomyopathyTransthyretin Amyloidosis

Acoramidis Transthyretin Amyloidosis Prevention Trial in the Young (ACT-EARLY) Study in Asymptomatic Carriers of a Pathogenic TTR Variant

RECRUITING
NCT06563895Phase PHASE3Eidos Therapeutics, a BridgeBio companyStarted 2025-05-12
AcoramidisPlacebo oral tablet
Clinical Literature
Open Research Assistant →
Full-Text Mentions
NLP-detected gene mentions in article bodies · via PubTator3
PubTator3
Top 5 full-text resultsSearch PubTator3 ↗
Key Publications
Landmark & review papers · by relevance
PubMed
Top 5 results · since 2015Search PubMed ↗