Genetic engineering is the artificial alteration of genes, involving the removal and insertion of DNA from different organisms, which creates recombinant DNA and leads to genetically modified organisms (GMOs). This process allows for cross-species gene transfer and has applications in agriculture, medicine, and pharmaceuticals, such as creating insulin-producing bacteria or transgenic animals. However, it raises ethical concerns regarding the release of GMOs into the environment, implications for food sources, animal welfare, and the potential misuse of genetic testing in humans.