Ah yes, everyone's favorite lecture, the inborn errors of metabolism. You meet a 5 year old with mental retardation who was just diagnosed with ectopia lentis (dislocated lens), which occurs in 90% of these patients; 60% have a inferior or nasal subluxation. There is a family history of this disease which seems to skip generations. The patient is at risk for osteoporosis and thromboembolism. Physical exam shows tall stature.
Challenge: What's the diagnosis?
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