Asperger's syndrome, X-linked mental retardation (MRX23), and chronic vocal tic disorder.

Pervasive developmental disorders are severe disorders of development with no consistent neurobiologic etiology and most often an idiopathic etiology. We report a 12-year-old male who met criteria for a pervasive developmental disorder (Asperger's syndrome) and a chronic tic disorder. The child also has an X-linked cognitive impairment (MRX23). The presence of tic symptomatology, pervasive developmental disorder, and fragile X syndrome has previously been reported. Since no singular etiology for Asperger's syndrome has been found, the possibility of other cases of Asperger's syndrome occurring with concurrent abnormalities on the X chromosome should be considered by clinicians, especially if tic symptomatology is present.