Screening for fragile X syndrome: results from a school for mentally retarded children.
Fragile X syndrome is the most common inherited form of familial mental retardation. The purpose of this study was to identify yet unrecognized fragile X individuals and to estimate the frequency of both the FRAXA and FRAXE forms of the disease in a population of mentally retarded children attending a special school in Croatia. The results are reported of molecular screening of 114 children with mild to severe mental retardation. Three individuals (2.6%) with the FRAXA form of the fragile X syndrome and one boy (0.9%) with FRAXE mental retardation were detected; a total of four newly diagnosed fragile X families were identified. Closer clinical examination revealed that behavioural and speech disturbances were clearly present among all fragile X cases (both FRAXA and FRAXE), indicating that these features could be additional diagnostic criteria for the preselection of individuals at risk.


CONCLUSIONS
Fragile X screening among mentally retarded children attending a special school should be highly encouraged to reveal the cause of mental retardation and to detect yet unrecognized fragile X individuals. The frequency of fragile X syndrome in a such population in Croatia was found to correlate with similar results from previous studies. However, since at the time of diagnosis all affected families had a second or even a third child born, earlier diagnosis should be considered to provide greater benefit to fragile X families.
Division of Molecular Medicine, Ruder Bosković Institute, Zagreb, Croatia. silva@icarus.wustl.edu
S
S
Hećimović
I Petek
IP
Tarnik
I
I
Barić
Z
Z
Cakarun
K
K
Pavelić
D000293:Adolescent; D002648:Child; D017523:Croatia / Q000453:epidemiology; D004495:Education of Persons with Intellectual Disabilities / Q000706:statistics & numerical data*; D005260:Female; D005600:Fragile X Syndrome / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D007361:Intelligence Tests; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data*; D015995:Prevalence; D016601:RNA-Binding Proteins / Q000032:analysis / Q000235:genetics; D012720:Severity of Illness Index
C096916:FXR1 protein, human; C096915:FXR2 protein, human; D016601:RNA-Binding Proteins