Alliende M Angélica, Cámpora Laura, Curotto Bianca, Toro Jessica, Valiente Alf, Castillo Marcela, Cortés Fanny, Trigo César, Alvarado Cecilia, Silva Manuel, Caru Margarita
Unidad de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Chile.
Rev Med Chil. 2008 Dec;136(12):1542-51. Epub 2009 Mar 23.
Mental retardation or intellectual disability affects 2% of the general population, but in 60% to 70% of cases the real cause of this retardation is not known. An early etiologic diagnosis of intellectual disability can lead to opportunities for improved educational interventions, reinforcing weak areas and providing a genetic counseling to the family.
To search genetic diseases underlying intellectual disabilities of children attending a special education school.
A clinical geneticist performed the history and physical examination in one hundred and three students aged between 5 and 24 years (51 males). A blood sample was obtained in 92 of them for a genetic screening that included a standard karyotype, fragile X molecular genetic testing and search for inborn errors of metabolism by tandem mass spectrometry.
This approach yielded an etiological diagnosis in as much as 29 patients. Three percent of them had a fragile X syndrome. Inborn errors of metabolism were not detected.
This type of screening should be done always in children with intellectual disability to establish an etiological diagnosis.
智力迟钝或智力残疾影响着2%的普通人群，但在60%至70%的病例中，这种智力迟钝的真正原因尚不清楚。智力残疾的早期病因诊断可为改进教育干预措施、强化薄弱环节以及为家庭提供遗传咨询创造机会。
探寻就读于一所特殊教育学校的儿童智力残疾背后的遗传疾病。
一名临床遗传学家对103名年龄在5至24岁之间的学生（51名男性）进行了病史采集和体格检查。其中92人采集了血样进行基因筛查，包括标准核型分析、脆性X分子基因检测以及通过串联质谱法筛查先天性代谢缺陷。
该方法为多达29名患者做出了病因诊断。其中3%患有脆性X综合征。未检测到先天性代谢缺陷。
对于智力残疾儿童，应始终进行此类筛查以确立病因诊断。
