This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
Mutation in Marfan's syndrome is? 
Select and explain. 
A. Collagen I, B. Collagen IV, C. Fibrillin I, D. Fibrillin II
C: Fibrillin I
Answer: C: Fibrillin I 
Explanation: Robbins and Cotran pathologic basis of disease South Asia edition. * Marfan's syndrome results from an inherited defect in an extracellular glycoprotein called fibrillin 1 by loss of structural suppo in microfibril rich connective tissues and excessive activation of TGF- beta signally Ref Robbins 9/e pg252