Fragile X syndrome.

Fragile X syndrome is the most important X-linked etiology of mental retardation and developmental disability currently known. Accumulating evidence also indicates that male and female carriers of the fragile X genetic abnormality demonstrate a relatively specific pattern of psychiatric disturbance. Fragile X males frequently manifest behaviors from the autistic spectrum whereas females show dysfunction in social interaction, thought processes, and affective regulation. In this review, an overview of the fragile X syndrome is presented with a focus on the occurrence of particular neuropsychiatric characteristics in males and females. Relevant data from recent genetic and neurobiological research is also described. The ability to study individuals with a specific genetic cause of psychopathology such as fragile X syndrome makes this condition of particular interest to biological psychiatry.