The wealthiest nation in the world is feeding its people an unhealthy diet—and growing most of this food using unsustainable methods.
Genetic engineering is the name of a group of techniques used to identify, replicate, modify and transfer the genetic material of cells, tissues or complete organisms. Important applications of genetic engineering in animal breeding are: The objective of this technology is to increase disease resistance, productivity and product quality in economically important animals by adding information of DNA markers to phenotypes and genealogies for selection decisions.
In spite of high expectations and new technical developments, its actual efficiency is not always high, as they require a thorough knowledge of functional genomics, and pose additional technical, economical and ethical problems. The possible role for cloning adult animals in breeding is also discussed.
Article Genetic engineering is the name of a group of techniques used for direct genetic modification of organisms or population of organisms using recombination of DNA.
These procedures are of use to identify, replicate, modify and transfer the genetic material of cells, tissues or complete organisms Izquierdo, ; Karp, Most techniques are related to the direct manipulation of DNA oriented to the expression of particular genes.
The most accepted purpose of genetic engineering is focused on the direct manipulation of DNA sequences These techniques involve the capacity to isolate, cut and transfer specific DNA pieces, corresponding to specific genes Lewin, ; Klug and Cummings, The mammalian genome has a larger size and has a more complex organization than in viruses, bacteria and plants.
Consequently, genetic modification of animals, using molecular genetics and recombinant DNA technology is more difficult and costly than in simpler organisms.
In mammals, techniques for reproductive manipulation of gametes and embryos such as obtaining of a complete new organism from adult differentiated cells cloningand procedures for artificial reproduction such as in vitro fertilization, embryo transfer and artificial insemination, are frequently an important part of these processes Murray et al.
Current research in genetic engineering of animals is oriented toward a variety of possible medical, pharmaceutical and agricultural applications. Also, there is an interest to increase basic knowledge about mammalian genetics and physiology, including complex traits controlled by many genes such as many human and animal diseases Houdebine, ; Lynch and Walsh, ; Montaldo and Meza-Herrera, ; Schimenti, ; Eggen, The interest in genetic engineering of mammalian cells is based in the idea of, for example, use gene therapy to cure genetic diseases such as cystic fibrosis by replacing the damaged copies of the gene by normal ones in foetuses or infants gene therapy Izquierdo, ; NHGRI, ; Coutelle and Rodeck, Genetically modified animals such as pigs will probably be used to produce organs for transplant to humans xenotransplantation Murray et al.
Other applications include production of specific therapeutic human proteins such as insulin in the mammary gland of genetically modified milking animals like goats transgenic animals, bioreactors Murray et al. These techniques may be used to increase disease resistance and productivity in agriculturally important animals by increasing the frequency of the desired alleles in the populations used in food production.
This can be accomplished by transferring alleles or allele combinations, over expressing or eliminating the expression of particular genes use of genetic engineering in animal breeding Woolliams and Wilmut, ; Cameron et al.
In addition, these techniques open the possibility of using artificially modified genes to increase the biological efficiency of proteins Kinghorn, The objective of this paper is to review some advances on genetic engineering applications in animal breeding, including a description of the methods, some applications and ethical issues.
Here I made emphasis in both the search and use of genomic information for selecting animals and to transfer and use their genes in commercial populations via marker-assisted selection MAS or transgenesis. This review focuses mainly in the methodology to apply genetic engineering directly to animals for genetic improvement.
Several important biotechnological applications such as the production of recombinant proteins in bioreactors Houdebine,disease diagnostic McKeever and Rege,feedstuff processing Bonneau and Laarveld, and production of vaccines Eloit,proteins, stem cells, tissues and monoclonal antibodies for use in therapeutics are not included here.
The impact of reproductive technologies on animal breeding, not directly related with gene transfer, are reviewed elsewhere Van Vleck, ; Visscher et al.
The possible role for cloning adult animals in breeding is also discussed Use of genomic information in animal improvement The use of genomic information sequences or DNA marker polymorphisms for the genetic improvement and selection of animals requires the knowledge of the effect of physically mapped genes with effects on economically important traits or quantitative trait loci QTL.
In MAS, the genomic information is combined with the classical performance records and genealogical information to increase selection accuracy, performing selection earlier in life and reducing costs Boichard et al.
The traits on which the application of marker-assisted selection can be more effective, are those that are expressed late in the life of the animal, have low heritability, are sex-limited, are expensive to measure or are controlled by a few genes.
Examples are longevity, carcass traits in meat producing animals, and diseases or defects of simple inheritance.Examples of Genetic Engineering By YourDictionary Genetic engineering is the process by which an organism’s genetic material is altered or selected so that the organism will have specific characteristics.
Genetic engineering has applications in medicine, research, industry and agriculture and can be used on a wide range of plants, animals and microorganisms. Genetic engineering has produced a variety of drugs and hormones for medical use.
New techniques of genetic engineering also for cultivation, since the current framework came into force. (The authorisation was later annulled.) The only GM crop currently allowed for cultivation, Monsantos MON maize, was against their application in human reproductive cells.
x They highlighted that research is needed to. 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 Human Genome Project At the center of genetic studies, with vast potential applications to genetic engineering, is the Human Genome Project (HGP), an international effort to analyze and map the DNA of humans and several other organisms.
Current genetic engineering techniques allow seg BIO-3 Use of Biotechnology in Agriculture—Benefits and Risks CTAHR — May mines the desirable trait is identified, it can be selected and transferred.
Similarly, genes that code for unwanted Use of biotechnology in agriculture--benefits and risks.