A new technology just announced today has the potential to wipe out diseases, turn back evolutionary clocks, and reengineer entire ecosystems, for better or worse. Because of how deeply this could affect us all, the scientists behind it want to start a discussion now, before all the pieces come together over the next few months or years. This is a scientific discovery being played out in real time. In the last few years, our ability to edit genomes has improved at a shockingly rapid clip.
These issues need to be considered by all stakeholders, including veterinarians, to ensure that all parties are aware of the ethical issues at stake and can make a valid contribution to the current debate regarding the creation and use of genetically engineered animals.
In addition, it is important to try to reflect societal values within scientific practice and emerging technology, especially publicly funded efforts that aim to provide societal benefits, but that may be deemed ethically contentious.
As a result of the extra challenges that genetically engineered animals bring, governing bodies Genetic engineering altering the face of started to develop relevant policies, often calling for increased vigilance and monitoring of potential animal welfare impacts 2. Veterinarians can play an important role in carrying out such monitoring, especially in the research setting when new genetically engineered animal strains are being developed.
Several terms are used to describe genetically engineered animals: In the early stages of genetic engineering, the primary technology used was transgenesis, literally meaning the transfer of genetic material from one organism to another. However, with advances in the field, new technology emerged that did not necessarily require transgenesis: For clarity, in the new CCAC guidelines on: There are 3 types of cloning: DNA cloning, therapeutic cloning, and reproductive cloning 3.
Reproductive cloning is used if the intention is to generate an animal that has the same nuclear DNA as another currently, or previously existing animal. The process used to generate this type of cloned animal is called somatic cell nuclear transfer SCNT 4.
During the development of the CCAC guidelines on: The different applications of genetically engineered animals are presented first to provide context for the discussion. Current context of genetically engineered animals Genetic engineering technology has numerous applications involving companion, wild, and farm animals, and animal models used in scientific research.
The majority of genetically engineered animals are still in the research phase, rather than actually in use for their intended applications, or commercially available. In addition to the insertion of foreign genes, gene knock-out techniques are also being used to create designer companion animals.
For example, in the creation of hypoallergenic cats some companies use genetic engineering techniques to remove the gene that codes for the major cat allergen Fel d1: Companion species have also been derived by cloning.
With the exception of a couple of isolated cases, the genetically engineered pet industry is yet to move forward. However, it remains feasible that genetically engineered pets could become part of day-to-day life for practicing veterinarians, and there is evidence that clients have started to enquire about genetic engineering services, in particular the cloning of deceased pets 5.
Wild animals The primary application of genetic engineering to wild species involves cloning.
This technology could be applied to either extinct or endangered species; for example, there have been plans to clone the extinct thylacine and the woolly mammoth 5. Individuals involved in field conservation often harbour suspicions that hi-tech approaches, backed by high profile publicity would divert funding away from their own efforts.
Examples include transgenic pigs and sheep that have been genetically altered to express higher levels of growth hormone 9.
Genetically engineered farm animals can be created to enhance food quality 9. Such advances may add to the nutritional value of animal-based products. Farm species may be genetically engineered to create disease-resistant animals 9.
Specific examples include conferring immunity to offspring via antibody expression in the milk of the mother; disruption of the virus entry mechanism which is applicable to diseases such as pseudorabies ; resistance to prion diseases; parasite control especially in sheep ; and mastitis resistance particularly in cattle.
Genetic engineering has also been applied with the aim of reducing agricultural pollution. The best-known example is the EnviropigTM; a pig that is genetically engineered to produce an enzyme that breaks down dietary phosphorus phytasethus limiting the amount of phosphorus released in its manure 9.
Despite resistance to the commercialization of genetically engineered animals for food production, primarily due to lack of support from the public 10a recent debate over genetically engineered AquAdvantageTM Atlantic salmon may result in these animals being introduced into commercial production Effort has also been made to generate genetically engineered farm species such as cows, goats, and sheep that express medically important proteins in their milk.The genetic engineering of animals has increased significantly in recent years, and the use of this technology brings with it ethical issues, some of which relate to animal welfare — defined by the World Organisation for Animal Health as “the state of the animal how an animal is coping with.
“Secondly, it’s altering things that are inherited, and that’s always been a bright line for genetic engineering.” Safety, too, will undoubtedly be a concern. Genetic engineering is used by scientists to enhance or modify the characteristics of an individual organism.
Genetic engineering can be applied to any organism, from a virus to a sheep. For example, genetic engineering can be used to produce plants that have a higher nutritional value or can tolerate exposure to herbicides.
Experts debate whether genetic engineering of unborn children, also called designer babies, would lead to a healthier society or eugenics. Genetic engineering is the science of altering living things by changing the information encoded in their deoxyribonucleic acid or "DNA".
Genetic information is stored in DNA using four different chemicals called adenine, cytosine, guanine and thymine. One of the leading researchers compares genetic engineering to the American and French Revolu tions or the birth of liberty.
All the old ideas are being thrown overboard. Genetic engineering has changed the pathway of biology more than any other single scientific event of the 20th century.