Objective: To describe a case of early-onset Alzheimer's disease (AD) in an apolipoprotein (Apo) ε2/ε2 homozygote.
Background: Apo ε2/ε2 is the rarest of the ApoE genotypes, representing only 1.4% of the population. Cognitive decline in ApoE ε2 homozygotes has rarely been reported.
Case report/methods: We report a 58-year-old Apo ε2/ε2 female who meets clinical criteria for probable AD as confirmed by neuropsychological testing, positron emission/computed tomography scan, CSF analysis and genetic screening for known mutations.
Results: The clinical course is typical of AD, with progressive cognitive and functional decline.
Conclusion: Clinically confirmed early-onset AD is atypical in ApoE2 homozygotes but can occur.
Copyright © 2010 S. Karger AG, Basel.