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GSC view of the ethics of animal cloning displays a common fallacy in the following opener from their ethics page.
"... cloning is simply the latest form of assisted reproduction, not all that different from artificial insemination and in vitro fertilization - which were also controversial when first introduced"
Asexual reproduction is very different from IVF and AI biologically, ethically and legally. This has been heavily discussed for the past 5 years. It is only "not all that different" if you presume a continuing technical trajectory of ever more intervention in animals for human ends, which presumes a number of questionable assumptions.
It is a classic statement of the ethical fallacy known as gradualism - the assumption that because (usually in the scientists' rather narrow terms) it is a logical step from what went before it is little different ethically. The fallacy is that one step can push you over an ethical edge without realizing it until you land at the bottom, as it were. Pigs hearts in humans and GM food are both examples where this logic was used and came seriously unstuck, because the proponents failed to relate the particular step to wider ethical norms.
Unlike AI and embryo transfer, which are manipulations in the detail of normal reproduction, nuclear transfer cloning of animals that normally reproduce sexually is a wholly artificial act with no correspondence in nature. In the light of the intrinsic value of all animals, regardless of whether suffering and welfare problems were overcome, we have argued that animal cloning would not normally be justifed, except in special circumstances where it enabled something of great moral value that could be achieved in no other way. GSC's ethical code provides no statement as to why, against a general trend to reduce experimentation involving animals, the company considers the activity of cloning pets to be ethically justified.
One example we consider acceptable is Roslin's original application, which was not for producing clones as such but to use the nuclear transfer method to enable better way of genetic modification for pharmaceuticals in the milk of farm animals to save human life. Another might be if cloning enabled a greater understanding and treatment of serious animal diseases, or perhaps to save an endangered species, although this seems unlikely to be a practicable on the scale that would be needed. Pig cloning for xenotransplantation is more controversial because of its other ethical and practical problems.
By comparison with these, cloning a pet ranks as an essentially cosmetic application which is not morally justified. Just because someone is rich enough to pay does not make it morally justified, and indeed suggests a trivialisation of embryo science in diverting skills and knowledge away from meeting serious ethical needs on to something that for many would represent an excessive commodification of the animal.
We would also oppose the use of cloning for more efficient animal production, for example for clone a prime breeding stock or to obtain greater reproducibility of cuts of meat. This would carry the mass production industrial logic too far into the realm of living creatures. These are not just identical widgets on an assembly line. Not everything we can do with animals is necessarily justified in the interests of efficiency.
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The Humane Society of the United States condemns the commercial cloning of companion animals. Given the current pet overpopulation problem, which costs millions of animals their lives and millions in public tax dollars each year, the cloning of pets has no social value and in fact may lead to increased animal suffering.
Cloning is an imperfect science and potentially dangerous for the animals involved, including the clone. Many animals cloned thus far have had a wide range of medical complications. Whether a cloned companion animal can lead a healthy and full life remains unknown. In addition, surrogate mothers who bear the cloned embryos until delivery may have to endure
surgical procedures due to complications from pregnancy.
For those looking to replace a lost pet, cloning will not create an animal identical to the one who is gone; cloning cannot replicate an animal's uniqueness. Cloning can only replicate the pet's genetics, which influence but do not determine his physical attributes or personality. In fact, a pet's personality, the specific trait that most owners would like to preserve and the attribute that most endears a companion animal to his family, is the trait least likely to be replicated by cloning. In addition, there is no guarantee the cloned companion animal will even physically resemble the original pet.
Components of DNA
DNA is a polymer. The monomer units of DNA are nucleotides, and the polymer is known as a "polynucleotide." Each nucleotide consists of a 5-carbon sugar (deoxyribose), a nitrogen containing base attached to the sugar, and a phosphate group. There are four different types of nucleotides found in DNA, differing only in the nitrogenous base. The four nucleotides are given one letter abbreviations as shorthand for the four bases.
- A is for adenine
- G is for guanine
- C is for cytosine
- T is for thymine
What is DNA?
The work of many scientists paved the way for the exploration of DNA. Way back in 1868, almost a century before the Nobel Prize was awarded to Watson, Crick and Wilkins, a young Swiss physician named Friedrich Miescher, isolated something no one had ever seen before from the nuclei of cells. He called the compound "nuclein." This is today called nucleic acid, the "NA" in DNA (deoxyribo-nucleic-acid) and RNA (ribo-nucleic-acid).
Two years earlier, the Czech monk Gregor Mendel, had finished a series of experiments with peas. His observations turned out to be closely connected to the finding of nuclein. Mendel was able to show that certain traits in the peas, such as their shape or color, were inherited in different packages. These packages are what we now call genes.
For a long time the connection between nucleic acid and genes was not known. But in 1944 the American scientist Oswald Avery managed to transfer the ability to cause disease from one strain of bacteria to another. But not only that: the previously harmless bacteria could also pass the trait along to the next generation. What Avery had moved was nucleic acid. This proved that genes were made up of nucleic acid.
August 08, 2008
Health Risks
According to a 2002 survey published in the science journal Nature Biotechnology, 23 percent of all cloned mammals produced by nuclear transfer—transplanting the nucleus of one cell into another—failed to reach healthy adulthood.
The survey showed that health problems in cloned animals range from mild to fatal, including obesity, anemia, heart defects, liver fibrosis, and respiratory failure.
The first cloned mammal—Dolly, a sheep—was euthanized last year because of a virus-induced lung tumor. The Roslin Institute in Scotland, which produced Dolly, said there is no evidence that cloning was a factor in the six-year-old sheep contracting the disease.
The survey showed that health problems in cloned animals range from mild to fatal, including obesity, anemia, heart defects, liver fibrosis, and respiratory failure.
The first cloned mammal—Dolly, a sheep—was euthanized last year because of a virus-induced lung tumor. The Roslin Institute in Scotland, which produced Dolly, said there is no evidence that cloning was a factor in the six-year-old sheep contracting the disease.
August 07, 2008
Animal Welfare Problems
The pattern of failures is varied. Most problems have been in pregnancy and shortly after. Typical examples have been over- or under-development of the placenta, unusually large foetuses, foetal deaths in pregnancy or shortly after birth. One possible explanation is that during embryo development there are certain genes which switch on and off for which it is essential that the male "imprinted" copy is used and some where it must be the female copy. These have to come from the right parent or they don't work. Faults may have arisen either because the nuclear transfer process did not work properly or the cell line from which the cells to be cloned may not be of the best quality. A very fundamental problem is that while skilled emprical work which has established what works and what doesn't, much of the basic science of mammalian nuclear transfer cloning remains uncertain.
Premature Ageing
It may not be premature ageing that is the issue so much as whether more conventional failures happen at a higher rate in cloned animals, and thus lead on average to shorter lifespans. There are relatively few cloned farm animals in existence, so it is difficult to say about longer term issues. Dolly is unique whether a problem like Dolly's arthritis is actually cloning or just a random effect. Roslin have a cloned sheep a year older and a year younger than Dolly who do not have arthritis, but these were not made from somatic cells. There would need to be several examples before a pattern were established. Roslin and PPL have other cloned sheep (although not from somatic cells) a year older and a year younger which do not have arthritis.
It's easier to see in mice because they have shorter time spans. Some cloned mice have been shown to die significantly younger than non-cloned ones, but since cloning in mice is rather different from larger animals, no one knows how general this would be.
It's easier to see in mice because they have shorter time spans. Some cloned mice have been shown to die significantly younger than non-cloned ones, but since cloning in mice is rather different from larger animals, no one knows how general this would be.
Do Cloned Animals have Shortened Life Spans?
The jury is still out. There is evidence that the length of the chromosome ends called telomeres are associated with ageing. Dolly has shorter telomeres than expected and so the suggestion is that the fact that she was cloned from a six year old ewe may have some effect. Significantly Dolly has given birth to three sets of lambs by ordinary mating, and they show normal telomere length. Other experiments in the USA claim that
cloning can produce longer telomeres, implying apparently younger animals.
This is an indication that, despite the empirical results, the basic science of nuclear transfer cloning is still comparatively little understood.
cloning can produce longer telomeres, implying apparently younger animals.
This is an indication that, despite the empirical results, the basic science of nuclear transfer cloning is still comparatively little understood.
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