The first genetically modified organism to be approved by the FDA was a form of yeast that was genetically modified to produce human insulin. For more than twenty years, almost all of the insulin used to tread diabetes has been produced by GMO yeast. Other genetically modified yeasts produce human clotting factor to treat hemophilia and human growth hormone for treating dwarfism.
Thanks to special interest groups, the subject of genetical organisms is subject to scare tactics, pseudoscience, and outright fabrications. Whether you are in favor of GMOs or not, it is worth fact checking any article you see on the subject.