A patient with a history of recurrent venous thrombosis is found to have a mutation in the gene encoding which of the following proteins?

A Protein C
B Protein S
C Factor V Leiden ✓
D Antithrombin III

Explanation

Factor V Leiden is a mutation in the gene encoding factor V, which makes it resistant to inactivation by activated protein C, leading to an increased risk of venous thrombosis.

Source

Harrison's Principles of Internal Medicine
Hematology Hematology: Coagulation Disorders Hematology: Coagulation Disorders Hard MEDICAL Confidence: high