Transgenic manipulation is the name of the game at GTC Biotherapeutics. The firm makes its products by inserting human DNA into animals who then produce the protein in their milk; the proteins are purified from the milk and used for human treatments. This process of creating what are known as recombinant proteins makes it easier and cheaper to produce large quantities of certain therapeutic proteins. The company's first commercial product, ATryn, received European regulatory approval in 2006 and FDA approval in 2009; the product is a recombinant human antithrombin designed to help prevent blood clots. GTC is a wholly owned subsidiary of French firm LFB Biotechnologies.