title: Screening of the mis-sense mutation producing the 717Val-->Ile substitution in the amyloid precursor protein in Japanese familial and sporadic Alzheimer's disease.
abstract: We investigated a C to T transition at base pair 2149 in the amyloid precursor protein gene in 41 Japanese cases of early-onset familial Alzheimer's disease (FAD), late-onset FAD and sporadic Alzheimer's disease (AD) by polymerase chain reaction and restriction enzyme polymorphism with BclI. Among 9 early-onset FAD patients derived from independent families, only one patient had the mis-sense mutation. Neither 5 patients with late-onset FAD nor 27 patients with sporadic AD had the mutation. Our result and the previous reports from Japan indicate that this type of mis-sense mutation is present in several cases of Japanese early-onset FAD. On the other hand, our data suggest that this mutation is not a common cause of Japanese early-onset FAD. Moreover, this mutation could be absent in late-onset FAD and sporadic AD in Japan. Because the mutation has been reported to be rare in Caucasian early-onset FAD and to be absent in Caucasian late-onset FAD and sporadic AD, the situation of this mutation in Alzheimer's disease may be common beyond the ethnic background.
authors.affiliation: Department of Neurology, Institute of Clinical Medicine, University of Tsukuba, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yoshizawa
authors.forename: Y
authors.initials: Y
authors.lastname: Komatsuzaki
authors.forename: H
authors.initials: H
authors.lastname: Iwamoto
authors.forename: H
authors.initials: H
authors.lastname: Mizusawa
authors.forename: I
authors.initials: I
authors.lastname: Kanazawa
mesh_terms: D000328:Adult; D000368:Aged; D000544:Alzheimer Disease / Q000145:classification / Q000453:epidemiology / Q000235:genetics*; D016564:Amyloid beta-Protein Precursor / Q000235:genetics*; D001483:Base Sequence; D005260:Female; D005820:Genetic Testing; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction
chemical_list: D016564:Amyloid beta-Protein Precursor