This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Hypercoagulability due to defective factor V gene is called - \nSelect and explain. \nA. Lisbon mutation, B. Leiden mutation, C. Antiphospholipid syndrome, D. Inducible thrombocytopenia syndrome', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Leiden mutation Of the inherited causes of hypercoagulability, mutations in factor V gene is the most common. Factor V mutations (called the leiden mutation) causes subsitution of arginine residue (at position 506) by glutamine. o This mutation makes factor V resistant to cleavage by protein 'C' (normally protein 'C' is one of the factor that regulates coagulation by inactivating factor V & VIII). o This results in unchecked coagulation.", 'role': 'assistant'}]