Animal Transgenic Technology

While modern technological advancements have greatly increased the issues facing the world's population, other areas of technology have significantly changed people's lifestyles and living conditions. As an illustration, the development of transgenic animal technology has significantly aided in reducing the impending obstacles in livestock production and revolutionized the medical and agricultural fields. The genetically engineered procedure used in transgenic animal technology is inserting a foreign DNA into an organism's embryo before birth in an effort to confer advantageous qualities. After a successful genetic engineering process, the resulting creatures display the new qualities, and they can pass the genes on to the next generations. In so doing, the desired beneficial traits would be helpful to the humankind in a variety of ways, including developing cures to fight the emerging and deadly diseases as well as producing cost-effective drugs. In a nutshell, transgenic animal technology plays a critical role in meeting the ever increasing demands of the global population, particularly by increasing the efficiency of livestock production, molecular farming, and minimizing environmental impacts.

History of Transgenic Animals Technology

Transgenic animal technology is a relatively recent innovation in the genetic engineering field dating back to 1973 when Stanley N. Cohen and Herbert W created the first transgenic animal (Pinkert 3). The two scientists mentioned above succeeded in altering the genetic makeup of E. coli by introducing a foreign gene from another type of bacteria. Two years down the line, in 1975, stakeholders held Asilomar Conference on recombinant DNA molecules in Pacific Groove, California. The agenda of the above meeting involved assessing the risks attributed to the research on recombinant DNA and recommending safety guidelines and procedures (Pinkert 3). The National Institutes of Health in the United States set strict guidelines to govern the pursuance of research on rDNA (Pinkert 3). In 1974, Rudolf Jaenisch, a professor of biology at Massachusetts Institute of Technology created the world's first transgenic mice by inserting SV40 viral DNA into the genome of the animals, without expressing rDNA. The mice in this study contained the SV40 leukemia genes which were also transferred to their offspring. In 1982, Ralph Brinster of the University of Pennsylvania carried out research on rDNA by inserting the structural genes for human growth hormone into the embryos of mice. According to the findings of the above research, Brinster noticed a significant difference in the size of a mouse with the foreign gene. Notably, the transgenic mouse grew larger in size compared to its counterparts.

Recombinant DNA Technology Overview

DNA or deoxyribonucleic acid plays a vital role in the development of transgenic organisms through its manipulation, hence the need is not only understand the genome but also how it is important in such development. DNA is a molecule that contains almost all the components of a cell, including proteins and ribonucleic acid (RNA) (Pray.51). DNA comprises all genetic information in segments called the genes. Scientists have managed to combine two or more strands of DNA through recombinant DNA technology (rDNA). The above technology, sometimes referred to as chimeric DNA, is fundamental in identifying, isolating, manipulating, and re-expressing genes from different species (Pray.51). In an attempt to ensure successful propagation of the DNA in host organisms, scientists often insert the rDNA into the system of a vector such as a virus, plasmid, artificial chromosome, or a cosmid (Pray.51).

Methods of Creating Transgenic Animals

While there are a variety of approaches in creating transgenic animals, this article discusses three widely used procedures. These methods include DNA microinjection, embryonic stem cell-mediated gene transfer, and retrovirus-mediated gene transfer. Since the inception of transgenic animal technology in the 1970s as manifested in the creation of the first transgenic animal by Stanley N. Cohen and Herbert W, scientists have made commendable steps in enhancing the efficiency of the procedure.

DNA Microinjection

The use of microinjection technology in creating transgenic animals was an efficient process in the early days as scientists found it reliable in introducing DNA into a cell (Niemann, Kues, and Carnwath 285). However, it is worthy to note that DNA microinjection was not used to create the first transgenic animal, a process that involved the use of virus delivery instead. DNA microinjection seeks to expose a fertilized egg to the transgene before the onset of the cell differentiation process. The above initiative helps in orchestrating the prevalence of the gene in the organism before the beginning of its development. DNA microinjection process involves the use of microtube suction device to hold a newly fertilized egg, and a separate ultra-fine glass needle to insert transgenic DNA into the male pronucleus. Upon successful experiment, the resultant organism after the procedure will have all its cells and tissues containing the essential gene inserted during the process. The egg and sperm used for this experiment undergo fertilization in vitro before the fusion of the two pro-nuclei inside the zygote as well as the microinjection of male pronucleus with the rDNA.

Although DNA microinjection technology has been efficient and prominent in the past, it has a fair share of its challenges. For instance, Rajoriya et al. (2013) pose that microinjection of foreign deoxyribonucleic acid (DNA) into the pronuclei of zygotes has presented such shortcomings like variable expression patterns, random integration, and low efficiency (241).

Embryonic Stem Cell-Mediated Gene Transfer

Unlike DNA microinjection which makes male pronucleus transgenic, embryonic stem cell manipulation uses the embryonic stem cells as its identity suggests. After undergoing in vitro fertilization, the embryo passes through culturing process to the blastocyst stage. The growth of the embryo takes approximately 5 to 7 days before harvesting the ES cells from the inner cellular mass. A variety of methods may be used to introduce the transgene after the culturing process. These procedures may involve chemical transfection, electroporation, viruses, as well as microinjection. The ES cells undergo screening to ascertain the cells containing the transgene. After identification of the ES cells mentioned above, the next step involves the insertion of the transgene-containing cells into the inner cellular mass of a new blastocyst, followed by the introduction of the manipulated embryo into the uterus of a pseudopregnant host. According to Moutsatsos, the determination of heterozygous offspring follows before breeding the two organisms to create a homozygous animal for the transgene (2001, p. 449).

ES cells enable the targeting of the exact location in the host genome where the transgene is inserted, a process made possible through the use of homologous recombination. Moutsatsos notes that regions of the DNA of the host organism undergo genetic engineering to flank the transgene, particularly in homologous recombination (2001, p. 449). Once the process of inserting of rDNA into the ES is complete, there is an exchange of the homologous DNA sites between the host chromosome and the rDNA, and therefore targets the transgene to the region. In this respect, it allows the insertion of transgenes into the active regions of the chromosome. It is notable that the several factors that manifest during the gene transfer process demonstrate the excellence of ES cells in creating transgenic animals. These attributes include the tolerance of the manipulation of in vitro cells, the ES cell pluripotency, as well as the capacity for homologous recombination (Rajoriya et al. 245). While ES cell manipulation has demonstrated success in creating transgenic mice, there is no existing literature to prove its use or success in the creation of larger animals (Rajoriya et al. 248).

Retrovirus-Mediated Gene Transfer

Retroviruses involve organisms which carry their genetic materials in RNA form rather than DNA. According to (Margawati, the retrovirus-aided gene technology includes the transfer of gene to the host cells using retrovirus as vectors (p. 10). The process mentioned above results in chimera, an organism consisting of cells from different zygotes. The retrovirus-mediated gene transfer process exhibits a recognizable difference in creating transgenic animals compared to the two methods discussed above. For instance, DNA undergoes a random insertion into the genome after its microinjection into the fertilized eggs. Besides, there may a disruption of the animal's gene function, an issue that can result in adverse health effects, including cancer, brain damage, and congenital disabilities among other health complications.

Importance of Transgenic Animals to Humans

The technology of transgenic animals presents excellent benefits to the humankind. It plays a critical role in addressing hunger and poverty among the global populace by increasing food production (Margawati 13). In agriculture, for instance, farmers have utilized the technology to breed specific animals with desirable traits such as increased milk or meat production (Wolf 615). The transgenic animal technology has enabled farmers to harvest high yields in a short time, thereby addressing food challenges currently witnessed in many parts of the developing world. Lastly, farmers can also adopt the technology in developing disease-resistant genes that would be inserted into the genome of the sick animals to cure certain diseases like influenza.

In the medical field, the technology has made it possible for scientists to cure certain diseases by inserting genes from healthy individuals into those of the sick people to treat a variety of illnesses. The Finish scientists are notable for creating a calf with a gene instrumental in promoting the growth of red blood cells in human beings (Lonberg 1118). Researchers have also applied the transgenic animal technology in the industrial sector. For instance, researchers have enhanced the safety of certain chemicals by producing toxicity-sensitive transgenic animals. The technology has also facilitated the production of many proteins that turn into enzymes. Such enzymes often perform several desirable functions in the human body (Lonberg 1120).

Application of Transgenic Animal Technology in the Contemporary Society

As discussed earlier on in this article, the transgenic animal technology is applicable in several sectors in the contemporary society, including the medical field, agriculture, industrial sector, as well as improving the human welfare. For instance, the technology has enabled the development of the transgenic animal model, an animal that has undergone genetic manipulation to display symptoms similar to diseases exhibited by human beings. In this respect, medical experts are now able to study the disease carefully, thereby increasing chances of getting the cure. Besides, the technology can also help in developing disease resistant gene which would be inserted in animals that are vulnerable to certain diseases to curb the prevalence of such disorders to the other generations. Besides, the technology can be applied in the food production such as breeding to bring forth animals with desirable traits, including increased milk production or healthy meat, an issue that can help the contemporary global population in tackling food shortages (Wolf 617).

Regulations on Transgenic Animal Technology

While regulations on animals derived from biotechnology in the past put much emphasis on the concept of food safety, animal health, and environmental impact, the current frameworks are considering stretching the regulations to encompass the emerging concerns. The high-level scrutiny by the global populace on the animal-derived foods and by-products calls for the adoption of stringent rules that neither facilitate nor restrict the use of such foods and by-products. For instance, Canada has developed an elaborate regulatory framework on biotechnology-derived animals. The Health Canada (HC) and Environment Canada (EC) have the responsibility of assessing food safety and environmental safety of the products and by-products from biotechnology-derived animals respectively. The Canadian Food Inspection Agency (CFIA) also plays a critical role in ensuring the safety of products and by-products mentioned above. Moreover, the Canadian Council on Animal Care (CCAC) also has the responsibility of overseeing the animals used for research, testing, and teaching (Kochhar, Adlakha-Hutcheon, and Evans 120).

In the US, for instance, the Animal and Plant Health Inspection Service (APHIS) of USDA is instrumental in regulating the use of livestock in testing, teaching, and biomedical research. Besides, the Food and Drug Administration (FDA) controls the anticipated products of animal biotechnology, including the use of the products (Kochhar, Adlakha-Hutcheon, and Evans 121).





Future Prospect for Transgenic Technology

Transgenic animal technology presents huge benefits to the global populace ranging from agriculture, medicine, through to the industrial sector, and its recognition among researchers and other stakeholders is enormous. In the agricultural sector, for instance, the empirical reality in the genetically modified livestock is real as the focus is now shifting to the commercial aspect of the technology. While the prospects of transgenic technology are highly promising, the issue of regulatory framework remains contentious as the possible effectiveness of the current regulatory model in governing the sector in the future is mysterious (Kochhar, Adlakha-Hutcheon, and Evans 120). The suitability, viability, and subsequent applicability of the existing marketing strategies in the future is also another issue of concern. Addressing the above issues will increase the consumer confidence and subsequent use of the animal products. In so doing, users may consider shifting from traditional food consumption to the modern science-based foods.

Conclusion

The introduction and subsequent use of transgenic animal technology among the global populations has presented considerable benefits. Scientists have used the technology in a variety of sectors, including medicine, agriculture, and industry to enhance the livelihood of the global populations through increasing food productivity, development of drug-resistant animals, and the creation of the first transgenic animal in the 1970s. Such changes in the transgenic technology aim at enhancing the efficiency of the initiatives as well as reducing the associated risks. DNA microinjection, embryonic stem cell-mediated gene transfer, and retrovirus-mediated gene transfer are some of the methods that scientists have used in creating transgenic animals in the recent past. The technology presents enormous benefits to the contemporary society, including increasing food production, the use of the transgenic animal model to study and cure human diseases, and livestock breeding among other advantages. Although there are existent regulatory frameworks on transgenic technology in particular countries, the global populace is yet to know and embrace the legislations. While the prospects of transgenic technology are promising as researchers and scientists shift from traditional food production, the regulatory frameworks remain an issue of contention and barrier in instilling consumer confidence.





































Works Cited

Kochhar, H. P., G. Adlakha-Hutcheon, & B. R. Evans. "Regulatory considerations for biotechnology-derived animals in Canada." Revue scientifique et technique (International Office of Epizootics), vol.  24, no. 1, 2005, pp. 117-125.

Lonberg, Nils. "Human antibodies from transgenic animals." Nature biotechnology, vol. 23, no. 9, 2005, pp. 1117-1125.

Margawati, Endang Tri. "Transgenic animals: their benefits to human welfare." American Institute for Biological Sciences, no. 2, 2003.

Moutsatsos, Ioannis K., et al. "Exogenously regulated stem cell-mediated gene therapy for bone regeneration." Molecular Therapy, vol. 3, no. 4, 2001, pp. 449-461.

Niemann, H., W. Kues, & J. W. Carnwath. "Transgenic farm animals: present and future." Revue scientifique et technique (International Office of Epizootics), vol. 24, no. 1, 2005, pp. 285-298

Rajoriya, Ravi, Sweta Rajoriya, & Nitesh Kumar. "TRANSGENIC ANIMALS: PROSPECTS FOR IMPROVING LIVESTOCK PRODUCTIVITY." J.Bio.Innov, vol. 2, no. 5, 2013, pp. 240-259.

Pray, Leslie. "Recombinant DNA technology and transgenic animals." Nature Education, vol. 1, no. 1, 2008, pp. 51.

Wolf, Eckhard, et al. "Transgenic technology in farm animals–progress and perspectives." Experimental Physiology, vol. 85, no. 6, 2000, pp. 615-625.