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Demystifying Animal Cloning: The Facts On Health, Regulatory And Safety Issues
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Cloning Breeds Healthy Animals
Cloning is one of several assisted reproductive technologies, including artificial insemination and embryo transfer, that allows farmers and other producers to replicate their best animals. The most common procedure today is known scientifically as somatic cell nuclear transfer (SCNT). SCNT involves transferring the genetic information from one animal and inserting it into an empty oocyte, or egg. The resulting embryo is implanted into a surrogate mother, who carries the pregnancy to term. This method is of commercial interest because many animals can be produced from a single donor. Decades of research has proven that cloned animals are just as healthy as non-cloned animals. In fact, according to a recent National Academy of Sciences review, "the health and well being of somatic cell clones approximated those of normal individuals as they advance into the juvenile stage… somatic cell cloned cattle reportedly were physiologically, immunologically, and behaviorally normal." /1 Cloning is simply assisted reproduction that produces a "twin" of the donor.
Extensive Study and Regulation Ensure Animal Cloning Safety
Animal cloning has been rigorously studied for decades, since the earliest research on embryo splitting in the late seventies and early eighties. /2 The US Food and Drug Administration has analyzed more than 40 scientific studies on the subject, conducted over 30 years and encompassing several generations and large families of livestock. The National Academy of Sciences has also scrutinized this topic, publishing reviews in 2002 and 2004. NAS concluded: "There is no scientific evidence that cloning is associated with any unintended compositional change that results in unintended health consequences in humans." /3 Regarding the offspring of clones: "no food safety concerns" would be posed by the progeny of cloned animals, because these animals were conceived by traditional means. Scientists have determined that any neonatal health problems related to cloning are caused by epigenetic events, or non-DNA related factors, that are not repeated in the offspring of clones. /4 FDA concluded: "The current weight of evidence suggests that there are no biological reasons…to indicate that consumption of edible products from the clones of cattle, pigs, sheep or goats poses a greater risk than consumption of those products from their non-clone counterparts." /5 More than 10 federal laws ensure public health and safety as animal cloning evolves. These include the federal Food, Drug & Cosmetic Act, Animal Health Protection Act, the Animal Damage Control Act and the National Environmental Protection Act. Overseeing these laws are three federal agencies: the U.S. Food and Drug Administration, the U.S. Department of Agriculture and the U.S. Environmental Protection Agency.
Animal Cloning Offers Safety Benefits for Consumers and Farmers
Cloning accelerates the reproduction of the healthiest and most productive livestock, allowing farmers and ranchers to breed top quality animals for food production. Healthy animals produce safe and healthy foods. Most consumers will likely never eat a cloned animal because clones are very costly, and will be few in number compared to their progeny. Accordingly, consumers will eat food from animals that are the progeny of clones, Throughout the global ecosystem, endangered species can be protected and preserved via animal cloning. In China, cloned panda cells are being kept on reserve should this species' numbers be threatened by extinction. Cloning allows us a new and powerful option to effectively deal with concerns about Bovine Spongiform Encephalopathy (BSE). Several research groups are working to produce cattle that have been genetically modified and are completely immune to BSE. Once these animals are approved for use in the U.S., cloning offers the only way to rapidly breed a BSE-proof herd from a single animal. Cloning is a vital part of the research being performed on animals to create milk with insulin or clotting factor IX to treat diabetics and hemophiliacs, respectively. Animals are also being bred to create immunizations against smallpox and anthrax. Cloning is essential because traditional breeding does not guarantee that genetic modifications will transfer to the offspring. Cloning can offer a tremendous advantage for farmers whose livelihoods depend on selling high-quality meat and dairy products. The breeding technique allows a greater number of farmers the ability to preserve and extend proven, superior genetics. Ranchers would also be able to select and propagate the best animals-beef cattle that are fast-growing, have lean but tender meat, and are disease-resistant. Those who use cloned animals have a distinct advantage because the process guarantees that desirable genetic traits will be passed on to offspring.
FAQs About Animal Well Being
- Won't these advanced breeding techniques make animals suffer?
The FDA has concluded cloning presents the same minimal risk associated with other accepted forms of assisted reproduction, such as embryo transfer. In fact, because these breeding techniques can improve the over-all health and disease resistance, cloning will greatly reduce animal suffering.
- Don't clones suffer a higher rate of deformities than other animals?
Only the placentas of clones show any difference from animals born the conventional way. These placental problems occur at similar rates in other assisted breeding techniques, such as in vitro fertilization and embryo transfer.
- Why do clones suffer from higher neonatal mortality rates?
The neonatal death rate of cloned animals approaches that of animals bred by in vitro fertilization or embryo transfer. Within 24 hours of birth there are no health differences. Because assisted breeding is used to reproduce extremely expensive breeding stock, these animals are typically delivered by caesarean section. Some researchers and breeders speculate these animals may not be full-term at delivery, which may account for some of the early health differences.
- How about in terms of the number of embryos used?
Embryos are lost in any form of reproduction, assisted or unassisted. In traditional breeding, animals lose an estimated one in four pregnancies in the first trimester. In cases of assisted reproduction, such as in vitro fertilization, embryo transfer, and cloning, the percentage is currently slightly higher.
- Did the famous cloned sheep Dolly live a full, healthy life?
Yes- in fact, Dolly grew and aged normally, and ultimately lived longer than most sheep until she died of old age. While she did develop arthritis, primarily due to her old age, this was unrelated to her origin as a clone.
- What about Dolly's shortened telomeres (structures at the end of chromosomes)?
Only one early study indicated Dolly, cloned from adult sheep cells, had shortened telomeres. This finding was never repeated in Dolly or other clones. Additional research indicates that cattle cloned from normal adult cattle cells possess normal telomeres.
- Is there a relationship between cloning and Large Offspring Syndrome (LOS)?
Scientists do not currently know how to prevent LOS, a problem that only affects cows. Because clones are "twins" of each other, they are affected by this as much as cattle produced by traditional breeding. At the same time, through the use of advanced reproductive techniques such as cloning, scientists are hopeful that they may find a solution to this Syndrome soon.
Footnotes
1/ National Academy of Sciences. Animal Biotechnology: Science Based Concerns. 2002. p 65.
2/ National Academy of Sciences. Animal Biotechnology: Science Based Concerns. 2002. p 63.
3/ National Academy of Sciences. Safety of Genetically Engineered Foods. 2004. p. 229.
4/ National Academy of Sciences. Safety of Genetically Engineered Foods. 2004. p. 220.
5/ U.S. Food and Drug Association. Animal Cloning: A Risk Assessment (Executive Summary). 2003.
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