Psychopathology in fragile X syndrome.

The fragile X syndrome is the most common known familial form of mental retardation. Young males commonly demonstrate hyperactivity and a short attention span, as well as physical abnormalities, some of which may lead to a diagnosis of Pervasive Developmental Disorder. Heterozygous females frequently demonstrate both a range of involvement with learning disabilities in math, and social anxiety. The more classical physical and behavioral features of this syndrome are reviewed.