“Genetic engineering poses moral and social dilemmas every bit as daunting as the rewards are enticing. —bioethicist Stephen P. Stich

Genetic engineering is the process of taking DNA from one organism and inserting it into another. The first instances of genetic engineering in the 1970s involved bacteria whose DNA could spontaneously recombine with other strains of bacteria—hence genetic engineering is often referred to as “recombinant DNA technology.” Since these first experiments in gene swapping between microorganisms, scientists have become more adept at splicing genes between organisms and even between species. Terms such as “gene transfer,” “gene therapy,” and “bioengineering” have been coined as these processes have become more sophisticated and precise.

Cloning is a new technology that is very closely related to genetic engineering. The cloning of a sheep in 1997 by researcher Ian Wilmut involved many...