Transgenic animals


The entry of a new product needs some degree of experiments in any field. The same is applicable in the field of medical biology, however, human subjects cannot be used to experiment medicine for the first time. Here comes the role of term transgenic animals. Transgenic animals are subjected to deliberate modification of their genome to try and test the efficacy of recombinant DNA technology. The intentional change in the is genetic makeup is not a  spontaneous mutation, but it is induced.  There is a chance that the animal could be harmed or even killed if the procedure is wrongly implemented. The major aim of the procedure is not to treat the animals but to utilize them as a medium of introducing the genetic materials.  The recombinant DNA is transmitted through the germ-line of the animal. Germ-line introduction help to distribute the effect of treatment evenly through all the cells. The most common transgenic animal is mice. Some of the other animals like rabbits, pigs, sheep, cows, and fish have also been proved to be good for transgenic experiments.


Table of contents

1. Introduction

2. Transgenic procedures

    2.1 DNA microinjection

    2.2. Retrovirus-Mediated Gene Transfer

    2. 3. Embryonic Stem Cell-Mediated Gene Transfer

3. Benefits from transgenic animals

    3.1 For genetic study

    3.2  In pathology

    3.3 As a product

    3.4 To test the vaccine safety:

4. Ethical concerns in transgenesis

     4.1 Regulations from governmental organizations:

     4.2. Patent rights violationBiopiracy):

5. Questions we need to address 

Transgenic procedures

1. DNA microinjection

This involves the transfer of a cloned gene combinations through injection. Cloning can be done by taking genes of 2 different species or the same species. Later on, the cloned gene combination is transferred to the pronucleus of a reproductive cell.

2. Retrovirus-Mediated Gene Transfer

A retrovirus is used as vectors to transfer the cloned and hybridized genetic material into the host cell. This can increase the chances of a high degree of biodiversity in the progeny.

3. Embryonic Stem Cell-Mediated Gene Transfer

This involves the prior insertion of the desired DNA combinations into an in vitro culture of embryonic stem (ES) cells. Stem cells are the primordial cells that later differentiated into somatic or germ cells. Consequently, the genetic material of every cell in the body is being altered.


Benefits from transgenic animals

Many transgenic animals are used to identify the safety of a particular medicine for the first time. Some of the laboratory tests, therapies, diagnostic tools cannot be directly implemented to human subjects. However, experimenting on the animals without knowing the outcome is ethically wrong hence every effort must be made to judge the outcome of an experiment in advance. Some of the reasons we use transgenic animals are: 


1. For genetic study:

This is done by genetically designing the animal`s genes. Doing this aid in understanding how genes are regulated and what are their influences on the human anatomy, physiology, development, and growth. For example, a study of ampicillin-resistant genes can be carried out by modifying the animal`s genes and then inject the drug to see it`s efficacy.

2. In pathology:

Pathology is a branch of medical science to study the disease causation and factors involved in the disease causation. The transgenic animals are so designed to enhance human understanding of disease causation. In the past, many transgenic models and applications have helped in identifying genetic disorders, blood disorders such as leukaemia, Alzheimer’s disease, etc. In the field of toxicology, it is used as a detective agency of toxins.

3. As a product:

Transgenic animals can be used to generate the most expensive biological products through DNA recombination. It is carried out by introducing a portion of artificially coded DNA to the target cells. It is predominantly used in the field of pharmaceuticals to understand the product efficacy. It helps to increase milk yield, meat production and the yield of livestock through injecting genetically engineered hormones. 

4. To test the vaccine safety:

For testing the vaccine safety, Guinea pigs and laboratory mice are transgenically used. Vaccines are injected to the animals at lower doses before using them in human subjects. This will help in understanding the adverse effects of a newly introduced vaccine. For example, the polio vaccine has been used this way. 


Ethical concerns in transgenesis

A. Regulations from governmental organizations:

It is important to obtain valid permission from the government and the administrative department of the concerned area before proceeding. One should understand that it is not an easy job to introduce a drug or DNA with a potentially risky for animals. Genetically modifying the organisms might even kill the host. Governemnt has set up organizations like GEAC (Genetic Engineering Approval Committee) to delimit the experiments and approve the operations only if they are immensely important at this stage.

B. Patent rights violationBiopiracy):

Biopiracy is the commercial use of biological resources without a legal license from the regulating bodies. When a product is indigenous to a territory or country, others cannot use them without buying the patent rights from where the product originated. One of the well-known example was the patent rights violation against Indian Basmati rice. India has around 27 documented varieties of Basmati rice. In the year 1997, one of the American companies purchased patent rights on Basmati rice through the US Patent and Trademark Office. This had no issues in reselling the imported grains in the US markets.


Some of the questions we need to address here when we experiment on an animal are​

1. Are we exploiting animal species by changing their natural form?

2. Are we trying to blur the lines between individual species by creating transgenic combinations?

3. Are we aware of future health risks associated with transgenics?

4. Are we really benefiting or harming mankind? 

5. Are we conducting transgenics for profit?

6. Are we trying to manipulate the whole nature of human beings one fine day so that we create physical or behavioural traits that may or may not be readily distinguished from what is usually perceived to be “human".?

7. Are we the reason for unintended personal, social, and cultural consequences at the end?





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