Figure 4. Association Between APOE4 and Biologically Defined Alzheimer Disease (AD) Spectrum Entities.
Relative frequency of APOE ε4 status (ε4 noncarrier/ε4 heterozygous/ε4 homozygous) in relation to the 4 biologically defined AD spectrum entities. APOE ε4 displayed a gene–dose association with both amyloid-β and tau-PET positivity. Zero percent APOE ε4 of homozygotes were A−T+. When excluding the 4 autosomal dominant AD cases, we observed a slightly lower frequency (17% vs 19%) of A+T+ in individuals who were APOE ε4 noncarriers.