Tamizaje mediante inmunohistoquímica del síndrome del cromosoma X frágil en unapoblación de ni？os y adolescentes costarricenses

aim: fragile x syndrome (fxs) is the most common form of inherited mental retardation. since it has no treatment, the screening of selected populations by fmrp detection is one of the most efficient preventive methods of the disorder. methods: the population consisted of 118 students attending special schools or referred by medical consultation. the percentage of fmrp expression was determined in hair roots and lymphocytes. all subjects who screen positive or borderline, were submitted to the molecular tests to determine the number of cgg repeats. results: we found no carriers of the full mutation by immunohistochemistry or molecular techniques. conclusion: the immunohistochemistry detection of fmrp is a low cost, reliable, fast, and simple technique, ideal for the screening of large populations.