Tanzi R E, St George-Hyslop P H, Haines J L, Polinsky R J, Nee L, Foncin J F, Neve R L, McClatchey A I, Conneally P M, Gusella J F
Nature. 1987;329(6135):156-7. doi: 10.1038/329156a0.
Amyloid beta-protein (AP) is a peptide of relative molecular mass (Mr) 42,000 found in the senile plaques, cerebrovascular amyloid deposits, and neurofibrillary tangles of patients with Alzheimer's disease and Down's syndrome (trisomy 21). Recent molecular genetic evidence has indicated that AP is encoded as part of a larger protein by a gene on chromosome 21 (refs 5-7). The defect in the inherited autosomal dominant form of Alzheimer's disease, familial Alzheimer's disease (FAD), has been mapped to the same approximate region of chromosome 21 by genetic linkage to anonymous DNA markers, raising the possibility that this gene product, which could be important in the pathogenesis of Alzheimer's disease, is also the site of the inherited defect in FAD (ref. 5). We have determined the pattern of segregation of the AP gene in FAD pedigrees using restriction fragment length polymorphisms. The detection of several recombination events with FAD suggests that the AP gene is not the site of the inherited defect underlying this disorder.
β-淀粉样蛋白（AP）是一种相对分子质量（Mr）为42,000的肽，存在于阿尔茨海默病和唐氏综合征（21三体）患者的老年斑、脑血管淀粉样沉积物和神经原纤维缠结中。最近的分子遗传学证据表明，AP是由21号染色体上的一个基因编码为一种更大蛋白质的一部分（参考文献5 - 7）。遗传性常染色体显性阿尔茨海默病（家族性阿尔茨海默病，FAD）的缺陷已通过与匿名DNA标记的遗传连锁定位到21号染色体的大致相同区域，这增加了这种可能在阿尔茨海默病发病机制中起重要作用的基因产物也是FAD遗传缺陷位点的可能性（参考文献5）。我们使用限制性片段长度多态性确定了FAD家系中AP基因的分离模式。与FAD的几次重组事件的检测表明，AP基因不是该疾病潜在遗传缺陷的位点。
