Abnormal behaviors of young girls with fragile X syndrome.

Mothers of 38 young girls with fragile X [fra (X)] between the ages of 4 and 11 years filled out the Child Behavior Checklist. Forty-seven percent of the girls had T scores greater than 70 on the hyperactive and social withdrawal scales. Between 26% and 15% of the girls also had high T scores on the depressed scale, on the schizoid-obsessive scale (for 6 to 11 year olds), on the schizoid or anxious scale (for 4 and 5 year olds), and on the aggressive scale. Although a high score on a scale of the Child Behavior Checklist does not constitute a medical diagnosis, it can alert clinicians to abnormal behaviors that warrant further assessment. These behaviors may also alert the clinician to the possibility of fra(X) syndrome when they are seen in their patients. The high percentage of girls with fra(X), who seem to have abnormal behaviors, provides good reason to diagnose them in their early years, not just for genetic counseling purposes, but so that they can receive appropriate intervention services.