The benefits of, and peoples concerns about, the use of recombinant DNA technology
Humans have used plants and animals for thousands of years, adapting many things to suit their requirements. The process of artificial selection, whereby only the organisms with the best characteristics are allowed to breed, genetically changes these organisms.
Recombinant DNA technology allows us much greater control over genetic manipulation. This can range from genetically engineered micro organisms, to genetically modified plants. In the former human genes can be inserted into bacteria and grown in fermenters. Which produces large quantities of human proteins such as insulin. Genetically modified plants can be made by transferring desirable genes from an organism to a crop plant.
For example, maize has been produced which is resistant to drought. Human proteins, such as haemoglobin, and blood-clotting factors, are already produced in the milk of transgenic cows, goats and sheep, due to the genetic modification of animals. Human gene therapy involves inserting a ‘normal’ gene into someone’s body to correct a genetic disorder. For example severe combined immune deficiency (SCID) leaves some people with almost no functioning immune system. The symptoms can, however, be cured by inserting copies of a gene coding for the enzyme adenosine deaminase (ADA) into their blood cells.
There are, however, many dangers arising from the release of genetically engineered organisms. The bacterium which is used in any genetic engineering experiments is E.coli which lives naturally in the human intestine. A modified strain of this bacteria could cause serious damage if it entered a human body.
Additionally, as bacteria are able to exchange genetic material with other species of bacteria, a strain of bacteria presently controlled by antibiotics, could become resistant and therefore extremely dangerous. These transgenic viruses and bacteria, which are at present perceived harmless, could mutate and become new pathogens which we are unable to control.
New viruses and bacteria are created every day in the search for new cures, some of these result in new and more dangerous strains. The Red Cross is calling for curbs on sensitive research, before lethal germs fall into the wrong hands. In September 2002 an unintentionally created lethal pig bacterium was stolen from a laboratory in the U.S. The Dean of the veterinary school, Lonnie King, said “We need more bio security, but at the same time we must keep doing this kind of research.” (New Scientist 14th September 2002). This theft shows how easily harmful pathogens can be obtained and why the ICRC (the world’s largest organisation for victims of conflict) is calling for controlled access to dangerous microbes and knowledge. Robin Coupland of the ICRC told New Scientist in September 2002: “The chances of catastrophe will only be reduced to a minimum by a whole series of measures”.
Before 9/11 and the anthrax attacks, most biologists would never have considered withholding results from publication, but now that is what governments across the world are asking them to do. Last year American researchers described how they made a polo virus from scratch by mail-ordering bits of DNA, and how this method could be adapted to make far more deadly viruses. In February 2002 scientists, funded by the US department of Defence, were told they may soon be required to submit their work for review before publication. Select all factors that are ways in which you might become the victim of a terrorist attack
I think this is a positive step towards national security, although a possible infringement of public freedom of speech and publication. Steven Teitelbaum, president of the Federation of American Societies for Experimental Biology, argues that any ban that goes beyond weapons research has rapidly diminishing benefit. While legitimate scientists would abide by a policy of secrecy, determined rogue states or terrorists might still get their hands on sensitive information. “By keeping more secrets we are placing ourselves in more danger. The information becomes more likely to get into the wrong hands before it gets into the right hands.” (New Scientist 18th January 2003.)
Claire Fraser, President of the Institute for Genomic Research in Maryland, wrote: “The ever-expanding microbial genome databases now provide a part-list of all potential genes involved in pathogenicity and virulence… from which to pick and choose the most lethal combinations.” (New Scientist 25th January 2003.) This again shows the ease with which information on bio weapons can be obtained.
Genes for herbicide resistance are inserted into crop plants in order for these crops to survive when strong herbicides are sprayed onto crops. There are concerns that this resistance gene may be able to spread from crop plants to closely related species of weeds, creating an “invincible superweed”.
“More than two-thirds of conventional crops in the United States are now contaminated with genetically modified material – dooming organic agriculture and posing a severe future risk to health.” (Geoffrey Lean)
This type of weed control obviously encourages the extensive use of herbicides, for which we know none of the long-term effects on soil, organisms or humans.
“British Scientists delivered a massive blow to the case for genetically modified crops yesterday when they showed in a trail-blazing study that growing them could harm the environment.” (Michael McCarthy)
Most of the research into the development of crops is often carried out by the companies producing the chemicals. Extensive chemical use would obviously be financially beneficial to those companies although dependence on chemicals, requiring large quantities of energy to produce, are not practical in the long run due to their finite supply. These companies make little attempt to investigate methods of farming which use less fertilisers and pesticides.
There is even the possibility genetically modified plants, altered for resistance against herbicides, could escape via pollen or seeds from test plots. These plants could become “super weeds” we are unable to control. For the first time, a fungus has been genetically modified to be more deadly to the weed it blights – unfortunately it kills crop plants as well. For example, herbicides cannot attack the velvetleaf weed alone due to its close relation to cotton. In theory, diseases are ideal for bio control because many just affect one plant species. While the GM fungus will not be released, it shows how genetic modification can have unpredictable results and why careful containment is essential.
“This is exactly the kind of unexpected consequence that opponents of genetic engineering warn about” says Jane Rissler of the Union of Concerned Scientists in Washington DC. “The business of putting in a toxin raises a red flag.” (New Scientist 28 September 2002.)
It is also more proof that biotechnology could be harnessed to create weapons that attack crops.
Some crop plants have been given a gene enabling them to produce a pesticide, and through natural selection this may accelerate the evolution of pesticide-resistant insects. Some believe that these transgenic organisms might set up an evolutionary process that could harm the environment. I, however, think it is unlikely that the consequences would be worse than the present extensive use of pesticides.
“Major new field tests should be done before any genetically modified crops are allowed to be grown commercially in Britain. Mps have told the government, days before ministers are expected to approve the commercial planting of a type of GM maize.” (BBC News Online by Alex Kirby) It says the trials on the maize were invalid, because the ordinary maize used as a comparison in tests with its GM equivalent was sprayed with a powerful weed killer, atrazine, which is to be banned across the European Union. The unanimous all-party committee report calls the trials “an unsatisfactory, indeed invalid comparison”, and says new trials should last at least four years. The drought resistant crop however, is believed less damaging to wildlife than its conventional version.
Populations of transgenic salmon have been produced in which individuals grow rapidly therefore producing a harvest much quicker. These transgenic fish could compete for food with other fish species, forcing them into extinction and therefore altering the food webs and the balance of nature.
Genetic Modification causes much controversy amongst religious groups as some sects cannot use products from specific organisms. For example, Hindus believe cows are sacred animals, and pigs are seen to be unclean by Jews and Muslims. People of these religions may object to products of specific transgenic organisms.
Genetic engineering could be used to insert genes into humans or their eggs and sperm. In some cases preventing an early death although potentially to give patients characteristics considered desirable. I believe this is morally wrong, as altering nature in humans may have many unpredictable results. On a large scale, a super race could be formed leaving natural society as a lower class. On a smaller scale, would these GM humans have a strict drug regime? If so, what would the effect of this be on their mental and physical state? How would the expense effect the already over-stretched NHS? It also reminds some people of programmes throughout history to eradicate less dominant ethnic groups.
Parents often face a dilemma after foetus screening, of whether to abort a baby with a genetic disorder. It will become possible to screen adults for genes that predispose them to genetic disorders. This might lead insurance companies to discriminate against people with these disorders, even though they are in perfect health.
“A person “at risk” for Huntington’s is automatically rejected for health insurance. The cost of a genetic screening for the disease is about $5,000 and is a very emotionally stressful procedure.” Says Cissy Bennett.
There are many concerns over recombinant DNA, but measures are being taken to contain some of the risks as more people become aware of them. Although it is obvious, some factors will remain a threat to the human race and its environment as long as research is continued regarding recombinant DNA.