Alliende, María AngélicaCampora, LauraCurotto, BiancaToro, JessicaValiente, AlfCastillo, MarcelaCortés, FannyTrigo, CésarAlvarado, CeciliaSilva, ManuelCaru, Margarita2015-01-122015-01-122008Revista Médica de Chile, Diciembre 2008, vol. 136, n° 12, p. 1542-1551http://hdl.handle.net/11447/33http://dx.doi.org/10.4067/S0034-98872008001200006Centro de Genética y GenómicaBackground: Mental retardation or intellectual disability affects 2% ofthe general population, but in 60% to 70% of cases the real cause ofthis 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 Aim: To search genetic diseases underíying intellectual disabilities of children attending a special education school. Material and methods: 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 tándem mass spectrometry. Results: 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. Conclusions: This type of screening should be done always in children with intellectual disability to establish an etiological diagnosis.spaFragile X syndromeGenetic screeningMental retardationArtículo