MUTATIONAL ANALYSIS OF THE AMYLOID PRECURSOR PROTEIN GENE IN JAPANESEFAMILIAL ALZHEIMERS-DISEASE KINDREDS

We sequenced the entire coding region of the amyloid precursor protein (APP) genes of 11 unrelated patients with Japanese familial Alzheimer 's disease (FAD) in order to determine the exact frequency of known AP P gene mutations and to search for novel mutations responsible for FAD . Three out of 11 (27.3%) FAD patients showed the known Val to Ile mis -sense mutation at codon 717, but no other mutations were detected in the entire coding region. Analysis of exons 16 and 17 in 30 Japanese w ith sporadic AD revealed no mutations. Moreover, there were no signifi cant differences in the allele frequencies of the DNA polymorphism in intron 9 among the 11 FAD, 39 sporadic AD, and 110 control subjects.