A boy has long limbs, lens dislocation upward and aortic root dilation. Which protein is defective?
Answer and explanation
Correct answer: D. Fibrillin-1
- Step 1: Marfan syndrome results from fibrillin-1 mutation. Answer: Fibrillin-1. Why not the others: Type I collagen causes osteogenesis imperfecta and type III Ehlers-Danlos vascular type.
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