Surveys from 274 families with at least one child with fragile X syndrome (FXS) were used to determine factors associated with the discovery of the diagnosis in a study at the University of North Carolina, Chapel Hill, NC. The average age at first concern was 15.6 months, professional confirmation was at 25.9 months, entry into early intervention or special services was at 32 months, the FXS test was ordered at 56.2 months, and the diagnosis was made at 60 months. Variability of the timing of these steps in diagnosis was considerable; the average age of diagnosis ranged from 6 months to 30 years. Children born later than 1990 were identified much earlier; for boys, the average age at diagnosis was 31.5 months. Girls were identified with FXS about 6 months later than boys. Many families had additional children with FXS before becoming aware of increased risk. Parents of children with FXS perceive the discovery of the diagnosis to take too long, leading to delays in interventional services, including counseling. Future solutions to the delay in diagnosis may include universal newborn screening. 
COMMENT. The authors predict that the diagnosis of FXS is a challenge to current criteria for newborn screening candidates. Despite the growing emphasis on early diagnosis of mental retardation syndromes, most children with disabilities are not identified at birth. Greater attention to parental concerns, and regular developmental screening might enhance the earlier diagnosis of children with disabilities.