While the genetic engineering of mouse models has allowed scientists to successfully understand and develop new therapies for many genetic diseases, the PWS mouse models generated so far have not fully mimicked the complexity of human PWS, slowing the progress in PWS research. Mouse models have long been the mainstay of biomedical research, but rat models are gaining popularity for a number of reasons. Advances in genetic engineering techniques have made the development of rats with genetic disorders much more efficient. In comparison to mice, rats may more faithfully mirror the human disease, particularly disorders involving the types of complex behavioral and cognitive impairments seen in PWS. Moreover, many investigators with expertise in obesity research work with rat models, and rats are the preferred species for drug development studies since their physiology is more similar to humans. These advantages have prompted FPWR scientists to prioritize the development of rat models of PWS as a means to advance the field. Thanks to a generous donation from Carol Hanna and Ed Korn, in honor of their daughter who has PWS, we will be able to develop this vital resource for PWS researchers. Two rat models, each with a disruption of a critical gene in the PWS region will be developed. The two genes to be targeted are SNORD116, which has been implicated in hyperphagia and obesity in patients, and MAGEL2, which appears to confer many of the clinically significant aspects of PWS,including obesity, intellectual disability, and autism http://www.fpwr.org/blog/research/13/10/game-changer-pws-genetics. Carol and Ed were looking for way to target their donation such that it would open new areas of study in PWS, and have long-lasting and important impacts on PWS research. The full characterization of these new rat models of PWS and their use in drug development promises to bring a host of new opportunities to understand and treat PWS. On behalf of the PWS community, FPWR would like to thank Carol and Ed for recognizing the value of these research tools with their generous donation.