Genetics has played an important role in the development of civilizations through artificial selection of plant and animal features. This type of genetic manipulation is called classical in reference to observations made by Gregor Mendel. Genetic engineering, often discussed in the context of molecular genetics, is a science involving the manipulation of genes either within the original organism (host) or between organisms (transgenic). Both branches of genetic study are based on an understanding that the genetic code for cells is contained in DNA (deoxyribonucleic acid) and that this material is the blueprint for all proteins made by cells. The code is generally universal, nearly identical in all living cells, allowing transfer of material between organisms.

Hybrid plants and animals created from both classical and molecular means form the base of much of the world’s foods today and genetic resources have become important commodities in world markets. Though concerns have been raised about the efficacy of germ plasm manipulation in non-human organisms, world attention has focused on the science more intensely as humans have become the center of genetic research. Within the shadow of attempted national eugenics programs during the Second World War, questions of ethics as well as law are intertwined with scientific advances brought about through the Human Genome Project, a worldwide collaboration to locate the more than 100,000 human genes by 2005, and the patenting of genetically engineered higher life forms. Indeed, this project moved ahead far faster than imagined, raising both profound ethical and “business” questions about the ownership of the mapped genome.

Though fictional films like Jurassic Park (1993; novel by Michael Crichton) depict a level of genetic engineering beyond current capabilities, the advent of Dolly the sheep cloned from her mother’s cells, focuses attention on implications of current research.

Popular notions of cloning that suggest a recreation of physical, mental and personality traits have given way to the reality that environment plays a large role in shaping the identity of an organism. The film Boys from Brazil (1978; novel by Ira Levin) illustrates the consequences of varying factors shaping personality Gene therapy and the production of medicines through genetic engineering have revolutionized modern medical practice. Gene therapy on humans began in 1990 and today nearly every medical school in the United States has at least one department working on gene-transfer research. Promising therapies for certain types of cancers and tumors, some forms of cystic fibrosis and diabetes, rheumatoid arthritis and hypercholesterolemia have spurred major pharmaceutical companies and the US government to invest billions of dollars into genetic research.

Such research is not without its downside. Population genetics is the study of the distribution of gene types within populations. With the advent of widespread and available genetic testing, the fear of genetic discrimination has increased. Such screening may lead to the documentation of genetic variations occurring without the presentation of symptoms. Such variations could be used to deny insurance or jobs based on the potential future manifestations of symptoms in individuals or offspring.