Transgenic animals are created using two main methods: DNA microinjection and manipulating embryonic stem cells. Examples of transgenic animals include GH-mice with increased growth, marathon mice with enhanced endurance, and goats producing the human blood clotting protein Antithrombin in their milk. Transgenic fish like GloFish have been genetically engineered to fluoresce for environmental monitoring. Mammalian cloning is done through nuclear transfer as demonstrated by Dolly the sheep. Transgenic technologies allow for applications like disease modeling and industrial production of human therapeutic proteins from the milk of livestock.