Pigs as model systems for biomedical research

Pigs have a long standing and very successful history as biomedical model for studying human diseases and developing novel therapies mainly attributed to the many genetic, anatomical and physiological similarities with humans. Non-transgenic pig models have long been used for a wide range of human organ systems and diseases, and even complex metabolic disorders and have served as model for developing novel surgical techniques and endoscopic approaches, such as NOTES (natural orifice transluminal endoscopic surgery). The availability of the porcine genome and novel tools to add or delete specific genes significantly expands the potential for transgenic pig production. Somatic cell nuclear transfer has emerged as the preferred method for transgenesis. Well characterized transgenic pig models have been reported for Cystic fibrosis, the eye disease Retinitis Pigmentosa, atherosclerosis and diabetes. Transgenic pigs have been produced for modeling neurological diseases, including Alzheimer and Huntington disease, specific forms of cancer, and skin diseases. Transgenic pigs play an important role in developing functional porcine xenografts to combat the growing shortage of appropriate human organs for transplantation. Other important transgenic pig models include immunodeficient pigs and Oct4/GFP transgenic pigs for studies of reprogramming. Pig models will not replace the already existing mouse models but can provide significant novel insight into a variety of diseases, as mouse models frequently do not mimic the human situation. Transgenic pigs will also soon play an increasing role in the development of novel therapies based on stem cell technology. The biomedical use of pigs will also facilitate transgenic pig production for agricultural production.