Molecular pathology of the fragile X syndrome.


Fragile X syndrome is the most common form of familial mental retardation (one in 1250 males and one in 2500 females, characterized by prominent dysmorphic features, macro-orchidism, and varying degrees of mental retardation. Diagnosis of this syndrome has relied on cytogenetic demonstration of the fragile site at position Xq27.3. A gene associated with the fragile X syndrome, FMR-1, has been isolated and mapped to the region of the X chromosome that corresponds to the region of the fragile site. Expansion of a trinucleotide repeat, CGG, and abnormal methylation of a CpG island account for the majority of mutations identified in FMR-1. These molecular characteristics have greatly enhanced the identification of affected individuals and carriers of the premutation who were not detected cytogenetically.

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@article{Tsongalis1993MolecularPO, title={Molecular pathology of the fragile X syndrome.}, author={Gregory J. Tsongalis and Lawrence M. Silverman}, journal={Archives of pathology & laboratory medicine}, year={1993}, volume={117 11}, pages={1121-5} }