A genetically modified organism (GMO) is an organism whose genetic material has been changed by genetic engineering. Genetic engineering involves the insertion, mutation, or deletion of genes in an organism. Genes inserted usually come from a different species. Many crops have been genetically engineered for a variety of reasons such as increased shelf life, ease of growth, improved shelf life, and increased nutrition. Some European countries do not accept shipments of genetically engineered organisms as the long-term affects are yet to be seen. The European Union has a ban on the approval of new genetically modified crops. Many crops grown in America are genetically engineered, especially corn and tomatoes.