The reader is referred to the paper by Atamna and Frey [13] for a discussion of Aβ and mitochondrial dysfunction in AD; that by Mahley and coworkers [14] for a discussion of the roles played by fragmented ApoE4 and mitochondrial dysfunction; and that by Stokin and Goldstein [15] for a discussion of the role played by APP in axonal transport and AD. Here, APP is linked to Alzheimer disease.