system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 4-year-old boy presents to his pediatrician for severe developmental delay. On exam he is noted to have macroorchidism, hypertelorism, large protruding ears, a large jaw, and a long thin face. Suspicious of what the diagnosis may be, the pediatrician orders a PCR and DNA sequencing. The results reveal an expansion of 250 repeats of CGG. What is the diagnosis of the boy?
assistant
Fragile X syndrome