Rapid advances in recombinant DNA technology have opened doors that previous generations never dreamed could exist. Recombinant DNA technology — also known as genetic engineering — combines the DNA from one organism with that of another to create a hybrid with specifically designed properties, such as a seed that's been made pest-resistant through the combination of animal DNA. This fast-growing technology presents a variety of potential benefits — and potential hazards.
Recombinant DNA has led to some revolutionary changes in the area of medicine. One example is its use in producing insulin, a life-saving necessity for people with type 1 diabetes. Purified insulin from cows and pigs was previously used, but recombinant DNA technology has allowed scientists to develop synthetic human insulin. Recombinant DNA has also been to develop vaccines for such diseases as herpes, influenza, hepatitis and other infectious diseases. The drug interferon, used to treat lymphoma and myelogenous leukemia, is also the result of recombinant DNA technology.
Another advantage of recombinant DNA technology is its use in agriculture. According to the website of the Human Genome Project, as of 2006 there were 252 million acres of transgenic crops planted in 22 different countries by 10.3 million farmers. Many of these were genetically engineered to be insect-resistant without the need for chemical herbicides, and some were developed to resist crop-destroying viruses and survive weather extremes. Genetic engineering was also behind the development of rice that contains increased levels of iron and vitamins, for use in Asian countries where chronic malnutrition is a problem. According to the site, new areas in development include bananas that produce vaccines to prevent infectious diseases and cattle that are resistant to bovine spongiform encephalopathy (mad cow disease).
One of the primary concerns over the use of recombinant DNA in food is that the long-term effects on human health are still unknown. In fact, a number of scientists have voiced their concerns about the potential health risks of this technology. According to British professor Mae Wan-Ho, bypassing conventional breeding with "artificially constructed parasitic elements [such as] viruses" may present hazards, since inserting foreign genes into a host genome has "been known to have many harmful and fatal effects, including cancer." Scientist Dr. Michael Antoniu notes that the artificial combination of "genetic material from unrelated species" is disrupting the genetic blueprint of the host organism "with totally unpredictable consequences," and he notes that recombinant DNA has resulted in the inadvertent production of toxic substances in "genetically engineered bacteria, yeast, plants and animals."
This technology also raises ethical concerns, particularly when human genes are inserted into nonhuman organisms that then become partly human. In China, human DNA is being placed in tomatoes and peppers to speed their growth. The question arises: Would eating a tomato that contained human DNA make you a cannibal? Famed physicist Stephen Hawking, while not a biotechnologist, points out that genetic engineering has caused a scientific shift in which we no longer merely explore the natural world and its mechanisms, but actually redesign them. DNA technology, he says, portends the end of natural evolution; for the first time in the history of humanity, our species can use science and technology to evolve our own genetic makeup.