ATryn is the brand name of the anticoagulant antithrombin manufactured by the Massachusetts-based U.S. company rEVO Biologics. It is made from the milk of goats that have been genetically modified to produce human antithrombin, a plasma protein with anticoagulant properties. Microinjection was used to insert human antithrombin genes into the cell nucleus of their embryos. ATryn is the first medicine produced using genetically engineered animals. GTC states that one genetically modified goat can produce the same amount of antithrombin in a year as 90,000 blood donations. GTC chose goats for the process because they reproduce more rapidly than cattle and produce more protein than rabbits or mice.
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