The following points highlight the five issues that are related to biotechnology. The issues are: 1. Dolly Sheep 2. Severe Combined Immunodeficiency 3. Bioreactor/Fermenter 4. Bioethics 5. Biopatent.
Issue # 1. Dolly Sheep:
Dolly (July 5, 1996V February 14, 2003), an ewe, was the first mammal to be successfully cloned from an adult somatic cell. She was cloned at the Roslin in Midlothian, Scotland, by Ian Wilmut and his team and lived there until her death at the age of six. Her birth was announced on July 5, 1996.
In April 1998, she gave birth to Bonnie and later three more lambs were born. On February 15, 2003 it was announced that Dolly had died from a progressive lung disease. The progeny is being studied to see if the detrimental effects are passed on to the offspring.
Technique used to create Dolly sheep is called as nuclear transplantation. Following are the steps involved (Fig. 1).
a. Udder cells of the donor ewe were taken and starved of nutrients to arrest cell division and to enhance totipotency.
b. From another sheep an unfertilised egg was taken and the nucleus of this cell was sucked out leaving behind the cytoplasm intact.
c. Now both the cells, i.e. cell from the udder and enucleated egg cell were placed to each other and gentle electric impulses were applied to allow fusion of the cells.
d. The resulting cell consisted of donor nucleus and triggered into the process of cell division.
e. It took six days for the cell to grow into an embryo.
f. After six days this embryo was implanted into the uterus of another sheep (surrogate mother).
g. After the gestation period was over, a cloned ewe was born, known as Dolly. Dolly was genetically identical or a clone of the original donor who supplied the nucleus.
Issue # 2. Severe Combined Immunodeficiency (SCID):
SCID occurs due to the defect in the gene for the enzyme adenosine deaminase (ADA). The reason for this defect is the deletion of gene for ADA synthesis. Patients suffering from SCID have non-functional, T-lymphocytes. Due to this they fail to respond against attacking pathogens.
It can be cured by the following way:
Bone Marrow Transplant:
Enzyme Replacement Therapy:
During the treatment, lymphocytes are extracted from the bone marrow of the suffering person. A good copy of human gene encoding this enzyme is introduced in such cells. Such cells are then grown outside the body in culture medium. A functional ADA-cDNA (using a retroviral vector) is introduced into such cells. After this, the cells are reinserted into SCID patient (Fig. 2).
Such patients need regular infusion on genetically engineered lymphocytes. A permanent cure can be achieved if a better gene is introduced into the bone marrow cells at an early embryonic stage.
Issue # 3. Bioreactor/Fermenter:
Basic structure of a bioreactor consists of a large stainless steel vessel of the capacity of 500,000 dm3. Around the tank is the jacket of circulatory water which helps in controlling the temperature of tank. In the centre is the agitator comprising of a series of flat blades which are rotated with the help of a motor. This helps in mixing of contents so that microorganisms come in contact with nutrients.
Aeration, temperature and pH control are also managed in the fermenter. For proper aeration, air is forced in at the bottom of the tank through a porous ring called sparger and the process is known as sparging. At the top of the tank is an outlet which removes waste gases and air. Material is introduced and withdrawn from the top of the fermenter through a number of inlet tubes called ports.
There are generally four ports depending on their use:
a. Inoculation port – introducing inoculum
b. Nutrient port – introducing nutrients
c. Antifoam port – adding antifoaming agent
d. pH port – adding acid or alkali to maintain optimum pH
At the base is present harvest line which is used to remove the culture medium and microbial product. To keep a regular check of pH and temperature change, tank is fitted with certain probes.
This bioreactor is also known as stirred tank fermenter (Fig. 3). This is a time tested design for large-scale production of microorganisms. Production of microorganisms in a bioreactor is done under aseptic and controlled conditions.
Small bioreactors are used in the laboratories for research purpose. The size can vary from 10-100 litres capacity. The only disadvantage of a bioreactor is that it is relatively costly because of its high energy requirement.
Issue # 4. Bioethics:
New varieties keep on arising in nature by the process of mutation but the frequency of such mutations is very low.
These days, farmers are accepting GM crop as it increases the yield and improves the economic status as well. It also supports healthcare and industry and provide food, feed and fibre security at global basis. However, care should be taken to reduce the environmental impact of such agricultural practices. The global community is already facing the important challenges associated with public perception of transgenic crops.
Ethics includes a set of standards by which a community regulates its behaviour and decides as to which activity is legitimate and which is not. So every community needs a set of standards formulated by them or their representatives so that community can work smoothly. With biotechnology, particularly rDNA technology it is necessary to control the exploitation of this technique.
The major concerns regarding GM crop and GM food are as follows:
a. The Risk of Transfers of Allergies:
There is a risk of transference of allergens (usually glycoproteins) from GM food to man and animal, e.g. peanuts and other nuts.
b. Pollen Transfer from GM Plants:
Pollen grains from GM crops can be transferred to related plant species and this can give rise to modified weeds. This process is known as gene pollution. If the gene for herbicide resistance gets incorporated in closely related plants it can increase its weediness.
c. Risk of Change in Fundamental Vegetable Nature of Plant:
Transgene from animals like mouse, fish or human are introduced in GM crops for molecular farming. There can be a risk for changing the fundamental nature of vegetable.
d. Effect of GM Crop on Beneficial and Non-Target Insects and Microbes:
It is natural for the microbes and insects to harbour on the plant surface and flowers. We need to study whether the changed metabolites are colonised by new microorganisms or not.
e. Effect of GM Crop on Biodiversity and Environment:
Since GM crops are artificially generated there is always a risk of harmful effects by them on biodiversity and environment.
f. The GM crops may bring about change in evolutionary pattern.
Regarding animal genetic engineering the following concerns are there:
i. Concern About Escape of Transgenic:
Transgenic animals may breed with the wild or domesticated animals. This causes risk of transfer of transgene to other populations.
ii. Risk for Escape of Retrovirus:
Retroviruses are used as vectors and there is always a risk of its escape from laboratories and transfer of gene to other animals.
iii. Risk of Human and Animal Health:
By the consumption of GM plants and product there is a risk of health problems like permanent allergies, etc.
iv. Ecological Concerns:
There is a major concern about the wide effects of producing disease resistance animals.
v. Use of animals in biotechnology causes great suffering to them.
vi. When proteins are generated from animals they are virtually reduced to factories.
vii. A line of thought feels that biotechnology is disrespectful to living beings as it exploits others for human welfare.
Issue # 5. Biopatent (Intellectual Property Rights – IPR):
Intellectual Property Rights is a collective term given to a number of different types of legal rights granted by each country. This can be considered as recognition for the contribution of the inventor, by the country to the development of a new technology, product and process.
When an invention is made it is necessary to get a patent for it before it can be brought in commercial use. Patent is granted by the government. The complexity in biotechnology patenting is that it involves the patenting of living organisms and products which are made naturally and normally are non-patentable.
Patenting can be done for the product, method or process, composition, new methods of treatment or diagnosis and new uses. Biopatent helps in economic growth of the country as well as the individual involved.