LEWY BODIES IN THE BRAIN OF 2 MEMBERS OF A FAMILY WITH THE 717 (VAL TO ILE) MUTATION OF THE AMYLOID PRECURSOR PROTEIN GENE

A second member of the original family with the valine to isoleucine s ubstitution at codon 717 of the amyloid precursor protein died after t he clinical diagnosis of Alzheimer's disease had been made in life. Ne uropathological examination of the brain revealed not only severe Alzh eimer type pathology, with senile plaques and neurofibrillary tangles, but also Lewy bodies both in the cortex and brainstem. Lewy bodies al so occurred in our first case, thus showing striking similarities in t hese two members of the same family. The possibility exists that the o ccurrence of Lewy bodies may not be coincidental, but could be genetic ally determined: the same genetic abnormality which determines the dep osition of beta A4 protein, thus triggering of a chain of events leadi ng to Alzheimer's disease, may result in, or predispose to Lewy body f ormation.