Pros and Cons of Gentic Engineering in Animals Essay
Pros and Cons of Gentic Engineering in Animals
GE, combined with cloning, can be applied to animals to make valuable pharmaceuticals which cannot be made in other ways. This is particularly useful for human proteins, which are produced in animal milk and used in ‘replacement’ and other therapies (e.g. lactoferrin in cows for treating septicaemia; alpha-1-antitrypsin in sheep for treating emphysema; factor IX in sheep for treating blood clotting disorders). Transgenic adult animals produced by this method show normal health and behavior. |Dozens, possibly many hundreds of sheep are mutilated and killed for these experiments. The lambs born are often excessively large or deformed and those that are not stillborn die when young. Research funds could be devoted towards finding ways of making the much needed protein pharmaceuticals in microorganisms. Because of the extra protein that has to be produced in the animals that have to be kept lactating optimally they are under constant metabolic stress. In order to minimize contamination from normal pathogens such as viruses, animals used to produce pharmaceuticals will have to be kept in abnormal conditions which violate their telos or intrinsic nature — this can cause suffering for the animal. |
Animals have been instrumentalized for millennia, e.g. the horse. Aren’t human lives of higher moral value than animal lives? GE of animals is strictly controlled by the cruelty to animals’ legislation of the country concerned and experimental protocols are carefully scrutinised by teams of experts.|GE instrumentalizes animals. Many countries have a ‘yes, but’ approach to permitting animal experimentation. Better control of experiments which cause suffering to animals would be achievable with the Dutch model of ‘no, unless’. Instrumentalizing animals means that they must first be objectified. Many scientists report emotional difficulties with what they have to do to animals. This shows that their objectification is incomplete.| Transgenic animals can be created so that their organs can be transplanted into human beings without being rejected by the normal immune processes (xenotransplantation). This is achieved by genetically modifying the cells in those organs to ‘look like’ human cells to the human immune system. Xenotransplantation is necessary because the demand for organs for transplant is far in excess of the supply from ‘donors’. If you are faced with death by heart failure or the offer of a pig heart transplant, which would you chose?|Xenotransplantation is placing great emphasis on heart transplants. But the diseased hearts being replaced have become so by lifestyles and diets which could have been changed in such a way as to avoid the need for a transplant in the first place.
There is a big risk when transplanting animal organs into human beings that animal diseases and dormant viruses in animal genomes could be transferred to the human population. Once activated they could cause uncontrollable epidemics for which medical science has no remedy. How much animal tissue must be transplanted into a human being before they can no longer be regarded as human and conversely, how many human genes can be transferred to, say, a pig before the pig is eligible for human rights? Transplantation in general raises the question: should we prolong life indefinitely simply because we can?| Transgenic or ‘knockout’ mice and other animals can be created with altered or missing genes so they can be studied as models of human disease or for testing possible useful drugs. |Many of these animals pass their lives in great pain and suffering. Animals are not good models for human diseases. Furthermore, there is no simple link between genes and disease. For instance when the human retinoblastoma (eye cancer) gene was inserted into mice it produced abnormalities but there were no symptoms of retinoblastoma. | Cloning, involving the transfer of almost entire genomes (cell nuclei), can be used to speed up the breeding of particularly valuable new varieties, using less valuable animals as surrogate mothers.|Cloned animals have chromosomes which show structural modifications equivalent to adult animals. Thus they are old before their time. ‘Dolly’ the sheep was ‘mutton dressed as lamb’.| GE can make new breeds of farm livestock more quickly with precisely determined characteristics such as leanness of meat or speed of growth.|Transgenic pigs with the human growth hormone gene inserted to make them grow faster were arthritic, ulcerous, partially blind and impotent (‘Beltsville’ pigs, USA). Producing breeds by GE creates too much wastage and suffering. Transgenic salmon with enhanced growth may escape into the wild, interbreed with wild salmon and so upset the genetics of the wild salmon population that it could be wiped out.| GE could be used in combination with cloning to save species from extinction thus maintaining global biodiversity. This is already under consideration for the Giant Panda in China. The techniques could also be used to recreate extinct species by cloning the DNA and inserting in suitable host cells. |Saving endangered species or salvaging extinct ones is merely science fiction. It tends to divert attention away from the challenges to biodiversity, namely the continuing destruction of habitats by human activity.|