FAMILIAL AND SPORADIC ALZHEIMERS-DISEASE - NEUROPATHOLOGY CANNOT EXCLUDE A FINAL COMMON PATHWAY

Whether all etiologic forms of Alzheimer's disease (AD) share a final common pathway is a major issue, We determined the severity and region al distribution of neuronal loss, amyloid plaques, neuritic plaques (N Ps), and neurofibrillary tangles (NFTs), and calculated the ratio of n euronal loss to NPs and NFTs in brains of 19 familial AD (FAD) patient s with linkage to chromosome 14, six AD patients with mutations of chr omosome 21 (codon 717 of the beta-amyloid precursor protein gene), and 11 sporadic AD (SAD) patients, There was no difference in the pattern of distribution of the various pathologic features or in the ratio of neuronal loss to NPs or NFTs in any AD group, However, FAD groups cou ld be distinguished from SAD by the greater severity and the lack of i nfluence of apolipoprotein E genotype on pathology, These differences may reflect differences in age at onset rather than different etiopath ologic mechanisms, The similarity of pathologic findings in the differ ent AD groups provides evidence for a final common pathophysiologic pa thway in AD.