Ever since Dolly the cloned sheep was born in Scotland in
1996, biotech scientists have had their sights on GM livestock.
'Cloning' can now refer to several procedures, but generally
involves removing a nucleus from the cell of an animal with desired
characteristics and inserting it into an egg cell whose own nucleus has been
removed. The restructured egg is then
stimulated to divide and form an embryo which is inserted into the womb of a
surrogate mother. If all goes well, the
pregnancy goes to full-term and a healthy, fertile offspring ensues.
For genetic engineers, that brief availability of the cell
nucleus of a future animal is a golden opportunity to insert a gene.
The procedure involves at least three animals: the nucleus
donor, the egg-cell donor, and the embryo recipient. Because the success rate is low, it also
involves multiple embryos and multiple sets of cell donors and surrogate
mothers. Add to this the veterinary
surgeons, drugs, field-station facilities and staff, specialist laboratories
and, of course, biotech scientists.
Clearly, cloning doesn't come cheap.
In fact, GM cloned animals come far too expensive to simply
eat.
The cloned outcome has to be a high-value, added-value money-spinner.
A lot of commercial interest has focused on GM cows to
generate high levels of pharmaceuticals or specialist 'human' proteins in their
milk [2]. But, although occasional GM
animal 'success' stories may be fed to the media, these are futuristic and the
actual extent of such research globally hasn't been documented.
GE Free New Zealand, however, has just compiled a report on 15
years of attempts by biotech company, AgResearch, to create GM cows producing
any one of six commercially-useful proteins in their milk.
The Report reads like a horror story of chronic suffering,
premature death, reproductive failure and slaughter (see below for more details,
unless you're squeamish).
Apart from the ethical issues which GM cows raise, there are
other fundamental problems with the outcomes.
For Example:
- The transgenic proteins aren't the same as the natural ones they're supposed to imitate. This raises questions of toxicity and allergenicity.
- Production of the desired transgenic protein (if any) was variable.
- The GM animals, if they survive at all, are not healthy. This outcome may improve with time and level of technical refinement, but questions of long-term health may always arise. Unstable product quality, including emergence of toxicity, allergenicity and harmful by-products, will feature in any unhealthy animals.
- The dream that a cow's genome could be genetically engineered to express the novel protein only in milk has so far remained a dream. Some the very few transgenic offspring produced nothing at all, while GM hormone-producing embryos were damaging to their surrogate mother and were badly hormone-damaged themselves. One GM product was found to be circulating in surrogate mothers' bodies for up to two years after her calf was born. Other surrogate mothers exhibited excessive health problems.
There's clearly nothing predictable about a GM embryo, a GM
pregnancy or a GM protein.
Also, questions of environmental pollution and horizontal
gene transfer from transgenic herds into, for example, soil and water microbes
remain to be addressed.
If you're asking yourself how this whole situation came
about, it may have been helped along by New Zealand government's decision to
disband its Ethics Committee in favour of agencies focused on environmental and
agricultural policies. Add to this that
the transgenic cows' development was in the hands of a commercial concern
which, unlike academic institutions, need not publish research findings to
justify its existence, and which can indulge in as much hyperbole about its
research as it needs to attract funding.
Although even AgResearch is now finding its funds stretched,
the emergence of genetic editing techniques [2] which can be used directly on
fertilised eggs and bypass all the problems inherent in cloning, seem set to
give it a new lease of life.
Some of the problems noted during experiments to create six types of GM cows:
- Average live birth rate was 0-7% (i.e. complete failure to very few).
Note. Dolly was the only survivor out of 277 attempts
at cloning.
- High incidence of spontaneous abortion, pregnancy failure and complications, premature birth.
- Calves demonstrated a high incidence of deformities, organ abnormalities and abscesses. Cancer was also noted, as were metabolic problems.
- Most of the very small number of transgenic offspring achieved were themselves sterile, and exhibited progressive chronic diseases such as cancer, arthritis, respiratory and metabolic problems, gangrenous mastitis, and abscesses in internal organs.
Note. Dolly
also suffered from progressive lung disease, arthritis and lung cancer although
the latter is reported to be common in this breed of sheep.
Besides the general natural inability of the GM cows to survive, there seems to have been slaughter on a grand scale, for example animals young and adult were euthanised due to excessive suffering, animals young and adult were culled as surplus to requirements or of no use, embryos were sacrificed to re-use their cells in future experiments.
If you want even more gory details, check out GE-Free
New Zealand's report (PDF download available here)
OUR COMMENT
A more rational alternative to GM pharm-cow biofactories and concomitant suffering is the continued use of the successful production techniques we already have, such as contained fermentation of GM and non-GM microbes.
A more rational alternative to the vast expenditure on GM animals is to devote the funds and scientific resources to developing sustainable agricultural practices.
SOURCES:
·
GE Animals in New Zealand - the first fifteen
years, 2000-2015, compiled by GE-Free New Zealand, 23.10.15,
www.gefree.org.nz
·
Transgenic cow research branded a
"disaster", Radio New Zealand News, 22.10.15
·
GE-Free New Zealand Press Release,
http://press.gefree.org.nz/press/20151023.htm, 23.10.15
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