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 2-year-old boy is brought to the physician by his parents for a well-child visit. During his last well-child visit 9 months ago, the patient had not begun talking. The parents report that their son frequently avoids eye contact and has no friends at daycare. He was born at term and has been healthy except for an episode of otitis media 6 months ago, which was treated with amoxicillin. His immunizations are up-to-date. He is at the 95 percentile for height, 20 percentile for weight, and 95 percentile for head circumference. He appears shy. His temperature is 37°C (98.6°F), pulse is 120/min, and blood pressure is 100/55 mm Hg. Examination shows elongated facial features and large ears. The patient does not speak. He does not follow instruction to build a stack of 2 blocks. Throughout the examination, he continually opens and closes his mother's purse and does not maintain eye contact. Which of the following findings is most likely to confirm the diagnosis?
assistant
CGG trinucleotide repeats on x-chromosome