The role of apolipoprotein E (APOE) genotype in early mild cognitive impairment (E-MCI) Risacher SL, Kim S, Shen L, Nho K, Foroud T, Green RC, Petersen RC, Jack CR, Aisen PS, Koeppe RA, Jagust WJ, Shaw LM, Trojanowski JQ, Weiner MW, Saykin AJ Frontiers in Aging Neuroscience April 2013 Open .pdf