脆性X染色体综合征是最普通的遗传性智力障碍疾病,以影响个体学习困难、行动障碍以及具有典型的体征而使人注意。1991年相应的突变基因被了解清楚后,该病已可明确诊断,也能对人群携带者进行普查。其病变基因位于X染色体的长臂上,分子发生变 Fragile X syndrome is the most common hereditary mental retardation disorder that draws attention to influencing individuals with learning difficulties, mobility disorders, and typical signs. After the corresponding mutant gene was clearly understood in 1991, the disease can be diagnosed clearly and the population carriers can be surveyed. The lesion is located on the long arm of the X chromosome, the molecular change