智力低下和孤独症男童脆性X基因突变的研究

目的应用改良基因检测方法,探讨脆性X综合征致病基因(fragileXmentalretardation"1,FMR1)在中国人群智力低下和孤独症中的作用。方法收集2002～2006年小儿神经、遗传代谢门诊诊断的男性孤独症患儿44例、非家族性智力低下男性患儿40例,建立适用于男性的FMR1基因突变检查方法,对检查阳性者以pfxa3探针进行Southern杂交。结果在44例孤独症患儿中,发现1例pfxa3杂交片段约0.2kb,为FMR1前突变;40例智力低下患者中FMR1基因未见异常。结论在孤独症人群中发现的1例FMR1基因前突变,其致病意义有待进一步阐明。

Study of fragile X mutation in mental retardation and autism in males

Objectives To detect fragile X mental retardation- 1 (FMR1) gene mutations in Chinese boys with mental retardation and autism with a modified genomic detecting technique. Methods Forty- four boys with autism and 40 boys with mental retardation who visited our hospital from 2002 to 2006 were studied. The genomic screening method for identifying the FMR1 gene mutations in male patients was established. Southern blot analysis by using the probe pfxa3 was performed subsequently. Results FMR1 gene mutation was found in 1 case with autism. Southern analysis showed that one pfxa3 fragment with an expansion of approximately 0.2 kb represented a FMR1 gene premutation. No FMR1 mutation was detected in other autistic patients and patients with mental retardation. Conclusions FMR1 gene premutation was identified in one boy with autism. The possible relationship between autism and the premutation needs to be further clarified. No full mutation of Fragile X gene was found in mental retardation and autism in this study.