[Mutation site of presenilin-1 gene in familial Alzheimer's disease].
OBJECTIVE
To explore the effect of mutation of presenilin-1 (PS-1) gene on the pathogenesis of familial Alzheimer disease (FAD).


METHODS
Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), denaturing high performance liquid chromatography (DHPLC), and DNA sequencing were used to detect the exons 4 and 5 of PS-1 gene of a 130-member family and a 50-member control group.


RESULTS
PCR-SSCP showed abnormality in PS-1 exon 5 among 5 AD patients and 4 AD family members without AD symptoms. DHPLC further showed double peaks in the electrophoretic curves of the above nine persons, indicating the possibility of mutation. DNA sequencing revealed a missense mutation of GCT to GGT in code 136 of PS-1 exon 5, leading to the substitution of Ala with Gly (Ala136Gly), in these 9 persons. No mutation in exon 4 was found among these subjects. Mutation in exon 4 and 5 was not found in other members of both this AD family and the control group.


CONCLUSIONS
The mutation in exon 5 of PS-1 gene, found in this AD family, may be one of the responsible PS-1 gene mutations for familial Alzheimer disease in Chinese.
Xu
Erhe
E
Department of Neurology, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053, China.
Jia
Jianping
J
Sun
Wenjun
W
D000544:Alzheimer Disease / Q000235:genetics / Q000473:pathology*; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004252:DNA Mutational Analysis; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D009154:Mutation; D020125:Mutation, Missense; D018807:Polymorphism, Single-Stranded Conformational; D053764:Presenilin-1
D008565:Membrane Proteins; C508853:PSEN1 protein, human; D053764:Presenilin-1; D004247:DNA