脆性X综合征(fragile X syndrome)的分子机理研究

Study of the molecular mechanism of fragile X syndrome

脆性X综合征(FraX)是一种常见遗传性智力低下的疾病,在我国人群的发病率仅次于Down氏综合征。细胞学上主要表现为Xq27.3处有一个脆性位点(FRAXA);分子水平上表现为FMR1基因5'端(CGG)n的异常扩增。从X脆性位点克隆到该病的致病基因FMR1,根据FMR1基因的特点,测定湖北人群中CGG重复序列,了解人群中FRA(X)位点(CGG)n的多态性,建立一种简便、快捷的检测方法。我们试图建立FMR-1基因超表达的细胞系和FMR-1基因表达被抑制的细胞系,确定FMRP功能。本研究对该病的筛查和诊断具有重要意义,也为阐明该病的发生机制和基因治疗提供依据。

Fragile X syndrome（FraX） is one of the most common hereditary diseases of mental retardation,its incidence rate just below Down′s syndrome.Frax has a fragile sites（FRAXA） in Xq27.3 in cytology,represent a gene FMR1,which is（CGG）n island abnormal amplification.FMR1 gene was cloned from fragile sites（FRAXA）,According to characterizaton of FMR1 gene,we measured the repeats of（CGG）n in Hubei human groups,to determine it′s polymorphism and set up a simple and quick genetic detection.We are trying to establish a FMR-1 gene overexpressin cell line and a knockout cell line,to test the function of FMRP.This study is meaningful for the screen and diagnosis of Fragile X syndrome（FraX）,and useful to understand its mechannism and supply a gene therapy foudation.