Large-scale APP duplication in early-onset Alzheimer's disease without cerebral amyloid angiopathy: A case report

Journal of Alzheimer s Disease Reports 2026 Open access

Read full text
Authors: Sho Shimohama, Shumpei Azami, Munenori Oyama, Tsubasa Takizawa, Masahito Kubota, Hisato Suzuki, Mamiko Yamada, Jin Nakahara, Daisuke Ito
DOI: 10.1177/25424823251412896
Cited by: 0
References: 29

Abstract

We present the case of a patient who began experiencing cognitive decline in her 30 s and was diagnosed with duplication of the amyloid precursor protein (Dup- APP ) associated early-onset Alzheimer's disease (EOAD). The diagnosis was supported by the presence of amyloid and tau biomarkers. The clinical course, neuroimaging findings, and genetic testing excluded other diseases known to cause early-onset cognitive impairment. Our case exhibited a markedly large duplication of 19 Mb and did not present with cerebral amyloid angiopathy. Our findings suggest a potential association between the size of the duplication and the clinical phenotype.

Fields of Study & Subjects

Fetal and Pediatric Neurological Disorders Genomics and Rare Diseases Alzheimer's disease research and treatments

Publication details

Journal / source
Journal of Alzheimer s Disease Reports
Volume
10
Pages
25424823251412896–25424823251412896
Publication date
1 January 2026
Language
EN