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West J Med. 1997 February; 166(2): 129–137.
PMCID: PMC1304031
Fragile X syndrome. Molecular and clinical insights and treatment issues.
R J Hagerman
Child Development Unit, Children's Hospital, Denver, CO 80218, USA.
Abstract
The fragile X syndrome is the most common inherited cause of mental retardation that is known. The prevalence of mental retardation from this syndrome ranges from 1 in 1,250 to 1 in 4,000 in the general population, although the prevalence of female carriers has been reported to be as high as 1 in 259. The discovery of the FMR1 gene mutation in 1991 has simplified diagnosis, enhanced our understanding of the spectrum of involvement in the fragile X syndrome, and stimulated research regarding the normal function of the FMR1 protein in brain development. Advances have also occurred in the treatment of the fragile X syndrome, and psychopharmacologic and educational interventions are reviewed here.
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