1 in a 1000

A 24 year old man presents to the health care system for the first time. He is feeling generally well and wanted to have a physical exam before his health insurance ran out. He has no past medical history, takes no medications, and has no allergies. His family history is notable only for breast cancer in his mother at age 40. He does not drink alcohol, smoke, or use drugs. He works at a local restaurant but may lose his job. He was told by his boss that he's socially awkward, has poor judgment, and doesn't learn from adverse experiences. As you talk to him, you note he has trouble sustaining attention. For the physical exam, you have him completely undress (shown below). You note that he has small, firm testes.

Challenge: You send genetic testing to confirm what disease?

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