APOE and Alzheimer disease: Despite the different morphologies of their cores, the p-FTAA stained <i>APOE</i> ε3/ε3 amyloid plaque cores had spectral properties identical to those of <i>APOE</i> ε4/ε4 plaque cores.<h4>Conclusions</h4>These data support the hypothesis that one mechanism by which the <i>APOE</i> ε4 allele affects AD is by modulating the macrostructure of pathological protein deposits in brain.