fragile X syndrome(redirected from Fragile X)
Also found in: Dictionary, Medical.
Related to Fragile X: autism, Down syndrome, myotonic dystrophy, Williams syndrome, Angelman syndrome, Rett syndrome
fragile X syndrome[‚fraj·əl ′eks ‚sin‚drōm]
A hereditary condition resulting from a trinucleotide repeat at an inherited fragile site on the long arm of the X chromosome. Affected males usually have some characteristic facial features, enlarged testes, and mental retardation. Females with on fragile X chromosome and one normal X chromosome may have a lesser degree of mental retardation.