散发性早发帕金森病患者Parkin基因的突变研究

A Study of mutations in Parkin Gene on sporadic early-onset Patients with Parkinson's Disease

目的:观察我国散发性早发帕金森病(Parkinson’s disease,PD)患者中是否存在parkin基因的突变以及突变的形式和分布,探讨parkin基因突变在PD发病机理中的可能作用。方法:病例组由35例散发性早发PD患者组成,70例正常体检者为对照组。以基因组DNA为模板,扩增parkin基因的全部12个外显子,然后分别采用琼脂糖电泳法观察外显子的大片段缺失及其分布和单链构象多态性(single-strand conformation polymorphism,SSCP)-DNA序列测定法确定外显子中点突变的存在和分布。结果:(1)在35例PD患者中发现外显子2、4缺失各1例,外显子3缺失2例;(2)4例SSCP泳动异常,测序证实1例患者的外显子7存在1个未曾报道过的新的点突变位点Gly284Arg。结论:parkin基因外显子缺失和parkin基因点突变也是我国早发性PD患者的致病原因之一。

Objective: To observe whether there were possible mutations in parkin gene and to determine the type and the distribution of those mutations in sporadic early-onset patients with Parkinson's disease(PD)in China and to explore the role of parkin mutations in the pathogenesis of PD. Method: 35 sporadic early-onset patients were recruited as subjects and 70 healthy subjects were included as controls. Genomic DNA from 70 normal controls and from those of PD patients were extracted from peripheral blood leukocytes with standard procedures. Several molecular biological methods were employed as follow: (1)the possible deletive mutations were detected by agarose electrophoresis; (2)the point mutations were screened by PCR-SSCP-DNA sequencing. Results: (1) Four patients were found to be carrier of exon deletions among them, the location of the deletion was on exon 2(1 case) ,exon 3(2 cases) and exon 4(1 case); (2)A new missense mutation (Gly284Arg)on exon 7 was found in a sample, while 4 samples exhibited abnormal mobility shift on SSCP electrophoresis from all subjects. ConclusionsThe deletive mutations and the point mutation from parkin gene have contributed to the development of sporadic early-onset Parkinson's disease in Chinese population.