In this article, You will read Biotechnology and Applications of Biotechnology – for UPSC IAS.
Biotechnology and its Applications
Biotechnology is the field that exploits living organisms to make technological advances in various fields for the sustainable development of mankind.
The European federation of biotechnology defines it as “The integration of natural science and organisms, cells, parts thereof and molecular analogues for products and services”.
Biotechnology is the use of an organism, or a component of an organism or other biological system, to make a product or process for a specific use.
It can include both cutting-edge laboratory techniques and traditional agricultural and culinary techniques that have been practiced for hundreds of years.
Brewing and baking bread are examples of processes that fall within the concept of biotechnology (use of yeast (= living organism) to produce the desired product).
- Such traditional processes usually utilize the living organisms in their natural form (or further developed by breeding), while the more modern form of biotechnology will generally involve a more advanced modification of the biological system or organism.
With the development of genetic engineering in the 1970s, research in biotechnology (and other related areas such as medicine, biology etc.) developed rapidly because of the new possibility to make changes in the organisms’ genetic material (DNA).
Biotechnology deals with industrial scale production of biopharmaceuticals and biologicals using genetically modified microbes, fungi, plants and animals.
The applications of biotechnology include therapeutics, diagnostics, genetically modified crops for agriculture, processed food, bioremediation, waste treatment, and energy production.
Beer brewing: In beer brewing, tiny fungi (yeasts) are introduced into a solution of malted barley sugar, which they busily metabolize through a process called fermentation. The byproduct of the fermentation is the alcohol that’s found in beer. Here, we see an organism – the yeast – being used to make a product for human consumption.
Penicillin: The antibiotic penicillin is generated by certain molds. To make small amounts of penicillin for use in early clinical trials, researchers had to grow up to 500 liters of “mold juice” a week. Here, an organism (mold) was used to make a product for human use – in this case, an antibiotic to treat bacterial infections.
IVF, or in vitro fertilization, is a technique used to help a woman get pregnant. It is when a human egg is fertilised with sperm in a laboratory. IVF is used to treat infertility and some genetic problems.
Gene therapy: Gene therapy is an emerging technique used to treat genetic disorders that are caused by a nonfunctional gene. It works by delivering the “missing” gene’s DNA to the cells of the body.
- In gene therapy, biological components from different sources (a gene from humans, a plasmid originally from bacteria) are combined to make a new product.
Tissue culture, a method of biological research in which fragments of tissue from an animal or plant are transferred to an artificial environment in which they can continue to survive and function.
Biotechnology has additional applications in areas such as food production and the remediation (cleanup) of environmental pollution.
Principles of Biotechnology
Genetic Engineering: Techniques to alter the chemistry of genetic materials (DNA and RNA) and to introduce these into host organisms and thus change the phenotype(observable physical properties of an organism) of host organisms.
Maintenance of Sterile (microbial contamination free) ambiance in chemical engineering processes to enable the growth of only desired microbe/eukaryotic cell in large quantities for the manufacture of biotechnological products like antibiotics, vaccines, enzymes, etc.
Genetic Engineering is a technique of manipulating the genome of the organism, to add one or more trait that is not found in organism naturally. Also, called gene manipulation /genetic modification.
- Isolation of genes: Desirable sequence of genes is obtained directly from the genome of normal cells or from other cells, which is achieved by cleavage and denaturation. DNA is extracted from cells.
- Synthesis of genes: Various methods are deployed for the same.
- Recombinant DNA: Cutting of DNA molecule at a desired position results in a new gene product which is called as recombinant DNA (r-DNA). The receiving organism is said to be transgenic. Using this technique, we can isolate and clone a single copy of a gene or DNA molecule into an indefinite number of copies all identical.
- Gene cloning: Isolation of gene and reproduction of a single copy of gene or DNA segment into the infinite number of copies all identical is known as gene cloning.
Hazards of Genetic engineering
- If a wrong DNA segment is inserted and it gets expressed, it can cause new diseases in human beings.
- It can be used in biological warfare.
- Genetical modification of existing species/recreation of extinct species can cause disaster
- New strains of bacteria/fauna can come out of the lab which can be hostile to human beings.
- Even in a single species, genetic engineering leads to the elimination of varieties – if some new disease comes up, the entire species may be wiped out.
National Genomic Grid
- Health Minister announced plans of Genomic grid for India-specific cancer research.
- In a move to take cancer research to the next level and make treatment viable for people of different economic classes, the government has plans to set up a National Genomic Grid, which will study genomic data of cancer patients from India.
- The grid to be formed will be in line with the National Cancer Tissue Biobank (NCTB) set up at the Indian Institute of Technology, Madras, and will collect samples from cancer patients to study genomic factors influencing cancer and identifying the right treatment modalities for the Indian population.
- The government plans to set up the National Genomic Grid in the same style with pan-India collection centers by bringing all cancer treatment institutions on board
- The grid will have four parts, with the country divided into east, west, north, and south.
National Cancer Tissue Biobank (NCTB):
- It is a joint initiative of the Department of Science and Technology (DST), Government of India, and Indian Institute of Technology, Madras.
- The NCTB is functioning in close association with the Indian Council for Medical Research (ICMR).
- NCTB, which has the capacity to stock 50,000 genomic samples from cancer patients, already has samples from 3,000 patients. The genomic samples will help researchers to have India-specific studies on cancers.
DNA and RNA
- DNA contains the sugar deoxyribose, while RNA contains the sugar ribose. The only difference between ribose and deoxyribose is that ribose has one more -OH group than deoxyribose, which has -H attached to the second (2′) carbon in the ring.
- DNA is a double-stranded molecule while RNA is a single-stranded molecule.
- DNA is stable under alkaline conditions while RNA is not stable.
- DNA and RNA perform different functions in humans. DNA is responsible for storing and transferring genetic information while RNA directly codes for amino acids and as acts as a messenger between DNA and ribosomes to make proteins.
- DNA and RNA base pairing is slightly different since DNA uses the bases adenine, thymine, cytosine, and guanine; RNA uses adenine, uracil, cytosine, and guanine. Uracil differs from thymine in that it lacks a methyl group on its ring.
Comparison of DNA and RNA
|1.||Deoxyribonucleic acid||Ribonucleic acid|
|2.||It occurs inside the nucleus of cell and some cell organelles but it plants it is present in mitochondria and plant cell.||It is found in cytoplasm of the cell but very little is found inside the nucleus.|
|3.||It is a double-stranded molecule consisting of a long chain of nucleotides.||It is single-strand helix having shorter chains of nucleotides.|
|4.||It stores and transfers genetic information to generate new cells and organisms.||It is used to transfer genetic code from nucleus to the ribosomes to make proteins and carries DNA blueprint’s guidelines.|
|5.||It has two nucleotide strands consisting of phosphate group, five carbon sugar (stable deoxyribose 2) and four nitrogen bases.||It is single stranded consisting of phosphate group, five carbon sugar (less stable ribose) and four nitrogen base.|
|6.||Nitrogen base pairs are Adenine links to Thymine (A-T) and Cytosine links to Guanine (C-G)||Here nitrogen base pairs are Adenine links to Uracil (A-U) and Cytosine links to Guanine (C-G).|
|7.||DNA is self replicating||It is synthesised from DNA when needed.|
|8.||The DNA helix geometry is in the form of B and can be damaged by exposure of ultra-violet rays.||The RNA helix geometry is in the form of A. It is more resistant to damage by ultra-violet rays.|
|9.||It is a long polymer chain.||It is shorter polymer.|
|10.||DNA produces regular helix i.e. it is a spirally twisted.||It produces secondary helix or pseudo helix as its stranded may get folded at places.|
|11.||It occurs in the form of chromosomes or chromatin fibres.||It occurs in ribosomes or forms association with ribosomes.|
|12.||Quantity of DNA is fixed for cell.||The quantity of RNA for a cell is variable.|
|13.||It is of two types: intra nuclear and extra nuclear.||It is of four types: m-RNA, t-RNA and r-RNA.|
|14.||Life of DNA is long.||Its life is short. Some RNA’s have very shorter life but some have longer but in all its life is short.|
|15.||After melting its renaturation is slow.||Fast|
Biological Functions of Nucleic Acids – DNA and RNA
- DNA is the chemical basis of heredity and may be regarded as the reserve of genetic information.
- DNA is exclusively responsible for maintaining the identity of different species of organisms over millions of years.
- A DNA molecule is capable of self-duplication during cell division and identical DNA strands are transferred to daughter cells.
- Another important function of nucleic acids is the protein synthesis in the cell. Actually, the proteins are synthesized by various RNA molecules in the cell but the message for the synthesis of a particular protein is present in DNA.
- It is known that every individual has unique fingerprints. These occur at the tips of the fingers and have been used for identification for a long time but these can be altered by surgery.
- A sequence of bases on DNA is also unique for a person and information regarding this is called DNA fingerprinting. It is the same for every cell and cannot be altered by any known treatment.
- DNA fingerprinting is now used–
- in forensic laboratories for the identification of criminals.
- to determine the paternity of an individual.
- to identify the dead bodies in any accident by comparing the DNA’s of parents or children.
- to identify racial groups to rewrite biological evolution.
- In 1953, scientists discovered the structure of DNA, and in 1972, researchers developed a method for cutting and splicing DNA. That method became known as recombinant DNA or rDNA.
- Recombinant DNA (rDNA) molecules are DNA molecules formed by laboratory methods of genetic recombination (such as molecular cloning) to bring together genetic material from multiple sources, creating sequences that would not otherwise be found in the genome.
- Recombinant DNA is possible because DNA molecules from all organisms share the same chemical structure. They differ only in the nucleotide sequence within that identical overall structure.
- In most cases, organisms containing recombinant DNA have apparently normal phenotypes(observable physical properties of an organism), That is, their appearance, behavior, and metabolism are usually unchanged.
The basic steps involved in Recombinant DNA Technology:
- Isolation of a DNA fragment containing a gene of interest that needs to be cloned (called as insert).
- Generation of a recombinant DNA (rDNA) molecule by insertion of the DNA fragment into a carrier DNA molecule called vector (e.g. plasmid) that can self-replicate within a host cell.
- Transfer of the rDNA into an E. coli host cell (a process called transformation).
- Selection of only those host cells carrying the rDNA and allowing them to multiply thereby multiplying the rDNA molecules.
- The whole process thus can generate either a large amount of rDNA (gene cloning) or a large amount of protein expressed by the insert.
- The first rDNA molecules to be generated using these procedures were established by the combined efforts in 1973 by the molecular biologists’ Paul Berg, Herbert Boyer, Annie Chang, and Stanley Cohen.
- The next step after a recombinant molecule has been generated is to introduce it into a suitable host.
- There are many methods to introduce recombinant vectors and these are dependent on several factors such as the vector type and host cell.
Some commonly used procedures are:
- Microinjection: In the procedure of microinjection, foreign DNA is directly injected into recipient cells using a fine microsyringe under a phase-contrast microscope to aid vision.
- Biolistics: A remarkable method that has been developed to introduce foreign DNA into mainly plant cells is by using a gene or particle gun. Microscopic particles of gold or tungsten are coated with the DNA of interest and bombarded onto cells with a device much like a particle gun. Hence the term biolistics is used.
Applications of recombinant DNA technology
- Recombinant DNA is widely used in biotechnology, medicine, and research.
- Recombinant DNA is used to identify, map, and sequence genes, and to determine their function.
Recombinant DNA is used to produce
- Human Insulin: Recombinant insulin is cheaper and easier when compared to insulin obtained from animal sources.
- Human growth hormone: For patients with pituitary glands generating an insufficient quantity of hormone for normal growth, this was a boon
- Blood clotting factor VIII: To help patients suffering from haemophilia.
- Herbicide and Insect-resistant crops: Commercial varieties like soya, sorghum, cotton have been developed. Such varieties integrate a recombinant gene that causes the resistance to herbicide glyph sate application
- Bacillus Thuringeinsis: is the name of the bacterium that naturally produces a protein with insecticidal properties
- Modern-day DNA profiling is also called STR analysis and relies on microsatellites rather than the minisatellites used in DNA fingerprinting.
- Microsatellites, or short tandem repeats (STRs), are the shorter relatives of minisatellites usually two to five base pairs long. Like minisatellites, they are repeated many times throughout the human genome, for example, ‘TATATATATATA’.
- In this era of genomics wherein, whole genomes of species are being sequenced and compared to get a vision into the fundamental nature of DNA, the blueprint of life, the ease with which DNA is sequenced has played a major role.
- The first methods for sequencing DNA were developed in the middle 1970s by Fred Sanger, and by Walter Gilbert and Allan Maxam.
- Subsequently, Sanger developed a new method that forms the basis of most DNA sequencing today.
- Sequencing DNA means determining the order of the four chemical building blocks – called “bases” – that make up the DNA molecule.
- The sequence tells scientists the kind of genetic information that is carried in a particular DNA segment.
Benefits of DNA Sequencing:
- Forensics: To identify a particular individual because every individual has a unique sequence of DNA.
- Determine the Paternity of the child
- Medicine: Used to detect the genes which are associated with some heredity or acquired diseases. As almost all organisms have some kind of genetic material we can understand the causes of all human diseases.
- Agriculture: Specific genes of bacteria have been used to make crops resistant against insects and pests. It is also useful in the production of livestock with improved quality of meat and milk.
Characterizing species of organisms using a short DNA sequence from a standard and agreed-upon position from the genome.
- Identification of plant leaves even in absence of fruit
- Identification of insect larvae
- Identification of products in commerce
- Lack of reliable information above the species level
- Gross oversimplification of the science of taxonomy.
Genome Sequencing is a laboratory process through which scientists get the complex DNA sequence (in terms of A,T,G,C) of an organism’s genome at a time. DNA containing cells such as saliva, epithelial cells, bone marrow, hair, seeds, and plant leaves are used as samples for sequencing.
Genome sequencing is done by an instrument called automated DNA sequences.
Do You Know?
- In a chromosome, there is a specific DNA sequence called the origin of replication, which is responsible for initiating replication.
- For the multiplication of any alien piece of DNA in an organism it needs to be a part of a chromosome(s) which has a specific sequence known as ‘origin of replication’.
- Thus, an alien DNA is linked with the origin of replication, so that, this alien piece of DNA can replicate and multiply itself in the host organism.
- Origin of replication (ori): This is a sequence from where replication starts and any piece of DNA when linked to this sequence can be made to replicate within the host cells. This sequence is also responsible for controlling the copy number of the linked DNA. So, if one wants to recover many copies of the target DNA it should be cloned in a vector whose origin supports a high copy number.
Human Genome Project (HGP)
The Human Genome Project (HGP) was an international scientific research project with the goal of determining the base pairs that make up human DNA, and of identifying and mapping all of the genes of the human genome from both a physical and a functional standpoint.
HGP and its benefits:
- Identification of predictive and predisposition markers would be accelerated by harnessing the huge amount of genetic variability available for common and complex diseases
- Data from the project is expected to answer several questions involving similarities and differences between humans and our closest relatives.
Specific Applications – Genome research could be potential helpful in other fields
- Improved diagnosis of disease and earlier detection of genetic predispositions to disease
- Rational drug design
- Gene therapy
- Reduce the likelihood of heritable mutations
- Access health damage and risks caused by radiation exposure to mutagenic chemicals and cancer-causing toxins.
Evolutionary Biology and Anthropology
- Study of evolution
- Study of migration of different human population groups
Energy and Environment applications
- Detect bacteria and other organisms that may pollute air, water, soil and food.
- Identify crimes and catastrophe victims.
- Match organ donors with recipients in transplant programs
- Development if productive and disease, insect and drought-resistant crops
- Healthier, more productive, and disease-resistant farm animals.
INDIAN GENOME VARIATION INITIATIVE
Network program initiated in 2003 and tenured for 5 years, by six constituent laboratories of CSIR. Aim was to provide information variation in subpopulations representing the entire country.
Indian Genome variation database: part of Indian genome initiative –aims to understand inherit genetic variability of the human subpopulation.
HUMAN GENOME PROJECT- WRITE
Genome Project – Write: is to write or build an artificial human genome with sophisticated bioengineering tools.
- To write the genetic code rather than read the genetic code
- Reduce the cost of engineering DNA segments synthetically in the laboratory
- Improving the ability to chemically manufacture DNA
- Growing transplantable human organs
- Engineering cancer resistance
- Engineering immunity to viruses
- Accelerating drug development
- Extent to which human life can or should be engineered
The human genome sequence of an Indian was mapped during 2009, putting the country in the league of then five others — United States, Britain, Canada, China, and South Korea — who had demonstrated similar capabilities. This means the 3.1 billion base pairs describing every function of the body of an Indian are now available for further study and as an important diagnostic tool for predictive healthcare.
Devoting over two years on the background work, a team of young scientists from the Indian Institute of Genomics and Integrative Biology (IGIB) in New Delhi mapped the genome sequence of a man in his fifties from Jharkhand.
The world’s first human genome sequence was completed in 2003 by the International Human Genome Project with scientists from the US, UK, France, Germany, Japan, and China. Resource constraints hindered India’s participation in that project.
- In recent years, a new technology, called DNA Microarray, has attracted tremendous interest among biologists.
- This technology promises to monitor the whole genome on a single chip so that researchers can have a better picture of the interactions among thousands of genes simultaneously.
- It is widely believed that thousands of genes and their products (i.e., RNA and proteins) in a given organism function in a complicated and orchestrated way that creates the mystery of life.
- However, traditional methods in molecular biology generally work on a “one gene-one experiment” basis, which means that the throughput is very limited and the “whole picture” of gene function is hard to obtain. Microarray Technology promises to study multiple genes in one experiment.
- Microarrays consist of large numbers of DNA molecules spotted in a systematic order on a solid substrate, usually a slide. The base pairing or hybridization is the underlying principle of DNA microarray.
- Microarray exploits the preferential binding of complementary single-stranded nucleic acids.
- A microarray is typically a glass (or some other material) slide, onto which DNA molecules are attached at fixed locations (spots).
- There are several names to this technology – DNA arrays, gene chips, biochips, DNA chips, and gene arrays. The DNA microarray technology is used for analyzing the expression of thousands of messenger RNA molecules.
This technique has been used to study the following:
- Tissue-specific genes
- Regulatory gene defects in a disease
- Cellular responses to the environment
- Cell cycle variations
- Gel Electrophoresis is a technique used to separate DNA fragments according to their size.
- Since DNA fragments are negatively-charged molecules, they can be separated by forcing them to move towards the anode under an electric field through a medium/matrix.
- Nowadays the most commonly used matrix is agarose which is a natural polymer extracted from seaweeds.
- The DNA fragments separate (resolve) according to their size through the sieving effect provided by the agarose gel. Hence, the smaller the fragment size, the farther it moves.
- The separated DNA fragments can be visualized only after staining the DNA with a compound known as ethidium bromide followed by exposure to UV radiation (you cannot see pure DNA fragments in the visible light and without staining)
- The separated bands of DNA are cut out from the agarose gel and extracted from the gel piece. This step is known as elution.
- The DNA fragments purified in this way are used in constructing recombinant DNA by joining them with cloning vectors.
- A short sequence of DNA with a known location on chromosome useful to identify cells, individuals or species
- To study the relationship between an inherited disease and its genetic cause, genetic markers can be used.
In medicine, a biomarker is a measurable indicator of the severity or presence of some disease state. More generally a biomarker is anything that can be used as an indicator of a particular disease state or some other physiological state of an organism.
A biomarker can be a substance that is introduced into an organism as a means to examine organ function or other aspects of health. For example, rubidium chloride is used in isotopic labeling to evaluate perfusion of the heart muscle. It can also be a substance whose detection indicates a particular disease state, for example, the presence of an antibody may indicate an infection.
Mitochondrial diseases are a group of disorders caused by dysfunctional mitochondria. Mitochondria are found in every cell of the human body except red blood cells.
Mitochondrial disorders may be caused by mutations (acquired or inherited), in mitochondrial DNA (mtDNA), or in nuclear genes that code for mitochondrial components.
They may also be the result of acquired mitochondrial dysfunction due to adverse effects of drugs, infections, or other environmental causes.
Production of cells or organisms originally derived from a single original cell or organism by the asexual method under laboratory conditions.
Process of making multiple molecules which is used to amplify DNA fragments containing whole genes. For gene cloning vectors (a small piece of DNA into which a foreign gene/DNA of interest can be inserted) are required.
Process of developing a population of identical cells from a single cell. Used in stem cell research.
A new multicellular organism is created which is genetically identical to another organism.
Dolly was the first mammal successfully cloned. First clones were frogs.
Scientists at India’s National dairy research institute Karnal Haryana produced the first cloned buffalo in 2009; however, the buffalo died few days later.
Types of Cloning
- Egg cell is placed into the uterus after few divisions in it. The cell is allowed to develop into foetus that is genetically identical to the donor of the original nucleus.
- Egg is placed in Petri dish to develop into embryonic stem cells which have shown potential for treating several ailments.
- It is also called somatic cell nuclear transfer or research cloning.
- In this technique, the resultant embryo is allowed to grow for 14 days. Its stem cells would then develop into human tissue or a complete human organ for transplant.
- Use of therapeutic cloning:
- Overcomes the problem of immune rejection which is a major concern in tissue transplantation
- Cell which are removed can give rise to all cells in the body except embryo i.e. it can treat diseases by replacing damaged cells
- Help in studying stem cells and future medical importance of it to treat against common diseases affecting today such as diabetes and Parkinson’s disease.
- Understanding the process of cancer formation
- Help in plastic, reconstructive and cosmetic surgery.
- Can solve the issue of infertility
- Can help save a life in case of kidney failure
- May be possible to reproduce sudden trait in humans via cloning
- Tamper with genetics in human beings, raises the probability of deliberate reproduction of undesirable traits.
- May violate social norms
- Endangers and exploits women: Put them on high risk of ovarian cancer, infertility.
RESTRICTION FRAGMENT LENGTH POLYMORPHISM (RFLP)
- Restriction Fragment Length Polymorphism is a technique that uses Restriction enzymes to identify variations in the homologous DNA sequences.
- The DNA isolated from an individual organism has a unique sequence and even the members within a species differ in some parts of their sequence.
- The restriction sites would also vary and hence if DNA from a given individual was subjected to digestion with a restriction enzyme the fragments generated would vary when compared with another individual’s DNA similarly digested.
- A major application of this technique is DNA Fingerprinting.
- Individuals except identical twins vary in their RFLP pattern as indicated schematically in the agarose gel electrophoresis.
- Hence the term DNA fingerprint is used and this is the basis of a major technique used in forensic science to identify and relate individuals.
GMO (GENETICALLY MODIFIED CROPS)
Genetically modified crops (GM crops) are plants used in agriculture, the DNA of which has been modified using genetic engineering methods.
Plants, bacteria, fungi, and animals whose genes have been altered by manipulation are called Genetically Modified Organisms (GMO).
GM plants have been useful in many ways. Genetic modification has:
- enhanced nutritional value of food, e.g., Vitamin ‘A’ enriched rice.
- made crops more tolerant to abiotic stresses (cold, drought, salt, heat).
- reduced reliance on chemical pesticides (pest-resistant crops).
- helped to reduce post-harvest losses.
- increased efficiency of mineral usage by plants (this prevents early exhaustion of fertility of soil).
In addition to these uses, GM has been used to create tailor-made plants to supply alternative resources to industries, in the form of starches, fuels and pharmaceuticals.
BT stands for Bacillus thuringiensis.
Bacillus thuringiensis is a gram-positive, spore-forming bacterium which is mainly found in the soil and hence it is also known as a soil-dwelling bacterium. This bacterium produces a protein that acts as a toxin for those insects destroying the yield. This bacterium is mainly used in the sprays for commercial agriculture and for organic farming. The use of this spray on crops is safe for the environment and causes no harm to the consumers.
The practice of using BT started in the year 1996 and began with using small quantities of genes from BT. With the help of this genetic transformation, plants used to create the necessary proteins to protect the crop from pests. All over the globe, in a land spanning 29 million acres, BT corn, BT potato, and BT cotton were grown in the year 1999. Relying on this technology alone, approximately 92 million dollars was saved by the United States.
How does the cry protein work?
- When an insect feeds on the plants, the cry protein present in the plants crystallizes the digestive system of insects and it starves to death since the cry protein is toxic to the organism’s digestive tract. Remember that it affects the insect’s digestive system and has no effect on the human digestive system.
Advantages of BT Crops.
- They help in controlling soil pollution as the use of synthetic pesticides are reduced when the plants begin to produce the toxins by themselves in their own tissues.
- BT Crops help in protecting the beneficial insects.
- Reduced manpower and labour charges.
- The pests hiding inside plant parts are controlled effectively.
- It is cost-effective as multiple sprays are not needed.
Disadvantages of BT Crops
- The BT crops are more costly than the normally grown crops.
- There is a possibility for allergic reactions while using these crops.
- BT Crops are not effective for certain pests including spider mites, seed corn.
POLYMERASE CHAIN REACTION
- The polymerase chain reaction or PCR as it is commonly known was invented by Kerry Mullis in 1985.
- It results in the selective amplification of a specific region of a DNA molecule and so can also be used to generate a DNA fragment for cloning.
- The basic principle underlying this technique is that when a double-stranded DNA molecule is heated to a high temperature, the two DNA strands separate giving rise to single-stranded molecules which can be made to hybridise with small oligonucleotide primers (single-stranded) by bringing down the temperature.
- If to this an enzyme called DNA polymerase and nucleotide triphosphates are added, much like what happens during replication, i.e primer extension occurs.
- This procedure is repeated several times ultimately results in amplification of the DNA stretch between the two primers (one on each strand of the DNA).
- A single PCR amplification cycle involves three basic steps of denaturation, annealing, and extension.
- In the denaturing step, the target DNA is heated to a high temperature, above 80 C which results in DNA strand separation.
- PCR-based diagnosis is faster, safer, and more specific – because it does not use live pathogens; instead, DNA from the infected tissue is isolated and the PCR technique is carried out using primers having specific complementary sequences to the pathogen DNA.
- It is interesting that archaeologists are using combinations of PCR and fingerprinting analysis to relate and establish ancient Egyptian dynasties from samples obtained from mummies.
GENETIC ENGINEERING APPROVAL COMMITTEE –INDIA
- The top biotech regulator in India is Genetic Engineering Appraisal Committee (GEAC).
- The committee functions as a statutory body under the Environment Protection Act 1986 of the Ministry of Environment & Forests (MoEF).
- It was earlier known as Genetic Engineering Approval Committee. Under the EPA 1986 Rules for Manufacture, Use, Import, Export, and Storage of Hazardous Microorganisms/Genetically Engineered Organisms or Cells, GEAC is responsible for granting permits to conduct experimental and large-scale open field trials and also grant approval for commercial release of biotech crops.
Molecular farming is a new technology that uses plants to produce large quantities of pharmaceutical substances such as vaccines and antibodies. It relies on the same method used to produce genetically modified (GM) crops – the artificial introduction of genes into plants.
A number of vaccines, antibodies, and other therapeutic substances made in plants such as tobacco, maize, potato, and carrot are already commercially available or in advanced clinical trials. Producing pharmaceuticals in plants is easy and efficient compared to conventional production methods.
Typically, animal or microbial cell cultures are used to produce vaccines but costs associated with maintenance, safety; storage and transport are 80% higher compared to plant-derived vaccines.
A genetically manipulated food containing organisms or related antigens that may provide active immunity against infection.
Edible vaccines against many microorganisms are being developed, with the goal of using them to vaccinate children in nonindustrialized countries where there are obstacles to the use of the traditional injectable vaccine.
Examples of Edible vaccines:
Transgenic Potatoes for Diarrhoea:
- They were tested and found to be effective, however raw potatoes are non-edible and cooking destroys protein antigens.
Advantages of Edible vaccines
- They are cheap therefore they can be mass-produced.
- They are stable at room temperatures.
- Need to process and purify do not occur
- Most importantly they trigger immunity at the mucosal surface. For e.g.: Those that line the mouth.
Disadvantages of edible vaccines
- Will the antigen be able to survive the hostile condition of the stomach and even if they will then be trigger immune system in the right way.
- Continued vaccine production might not be guaranteed due to changes in plants
- Glycosylation in patterns in plants differ from humans and could affect the functionality of vaccine.
THREE PARENT BABY/MITOCHONDRIAL GENE THERAPY
The procedure replaces a small amount of faulty DNA in a mother’s egg with healthy DNA from a second woman, so that the baby would inherit genes from two mothers and one father. The idea is to prevent certain genetic diseases being passed on to children.
Britain became the first country to allow for a three-parent baby and in 2017 the first 3 parent baby was born.
- Several people argue that this leads to designer babies
- Unsure about future risks child may face as Mitochondria is still not completely understood.
MICROBIAL FUEL CELLS
A microbial fuel cell (MFC) is a bio-electrochemical device that harnesses the power of respiring microbes to convert organic substrates directly into electrical energy.
At its core, the MFC is a fuel cell, which transforms chemical energy into electricity using oxidation-reduction reactions.
The key difference of course is in the name, microbial fuel cells rely on living biocatalysts to facilitate the movement of electrons throughout their systems instead of the traditional chemically catalyzed oxidation of fuel at the anode and reduction at the cathode.
Current and future uses for Microbial fuel cells
- Wastewater treatment– Microbial Fuel Cells can be utilized to treat sewage water. MFCs can kill the bacteria found in sewage
- Sea Water Desalination– Microbial Fuel Cells are capable of producing energy but at the level where we can remove salt from a large amount of water. However, there is potential for such a process to be accomplished, by using an adapted microbial fuel cell would make desalination of seawater possible without external electrical sources.
- Hydrogen Production– With the help of a Microbial fuel cell, hydrogen can be produced. This process does require an external source of power to convert the bacteria into carbon dioxide and hydrogen gas.
BIOTECHNOLOGY INNOVATION ORGANIZATION (BIO)
BIO is the world’s largest trade association representing biotechnology companies, academic institutions, state biotechnology centers, and related organizations across the United States and in more than 30 other nations.
BIO members are involved in the research and development of innovative healthcare, agricultural, industrial, and environmental biotechnology products.
Do you know?
- The Biotechnology Innovation Organization (BIO) BIO 2017 was held in San Diego, the USA in June, 2017.
- India Biotech Handbook 2017, showcasing the strengths of India’s fast-growing $ 42bn bio-economy was released in BIO International Convention 2017.
A biological product or medicine that is intended to treat diseases so rare that sponsors are reluctant to develop them under usual marketing conditions.
- In 1983, the US government passed the Orphan Drugs Act to stimulate research in the treatment of diseases that have been largely ignored by the pharmaceutical industry. Similar laws have been enacted in Japan, Australia, and the European Union. All these laws offer incentives such as shorter clinical trials, extended exclusivity, tax breaks, and high rates of regulatory success. They have made it commercially attractive for pharmaceutical companies to invest in the research and development (R&D) required to find a cure for these diseases. India does not have a nationwide Orphan Drug policy.
- In 2016 Karnataka became the first state to release a Rare Diseases and Orphan Drugs Policy. It recommended the implementation of preventive and carrier testing as a means of reducing morbidity and mortality. Given that over 80% of rare diseases have a genetic basis, it suggested the use of genetic testing to accelerate the identification of the critical genes involved in rare diseases.
Do you know?
- The court made many suggestions to the government. It pointed to the corporate social responsibility (CSR) provisions under the Companies Act, 2013, and confirmed that the act of sponsoring the treatment of rare diseases would qualify as a CSR activity.
It is the process of discovery and commercialization of new products based on biological resources. Despite indigenous knowledge being intuitively helpful, bioprospecting has only recently begun to incorporate such knowledge in focusing screening efforts for bioactive compounds.
Biopiracy is the term used to refer to the use of bio-resources by multinational companies and other organizations without proper authorization from the countries and people concerned without compensatory payment.
Biomining is a technique of extracting metals from ores and other solid materials typically using prokaryotes or fungi. These organisms secrete different organic compounds that chelate metals from the environment and bring it back to the cell where they are typically used to coordinate electrons.
- The people of India in a variety of ways have used neem, since time immemorial. Indians have shared the knowledge of the properties of the neem with the entire world. Pirating this knowledge, the USDA and an American MNC W.R. Grace in the early 90s sought a patent (No. 0426257 B) from the European Patent Office (EPO) on the “method for controlling on plants by the aid of hydrophobic extracted neem oil.” The patenting of the fungicidal properties of Neem was an example of biopiracy.
A biomaterial is a substance that has been engineered to interact with biological systems for a medical purpose, either a therapeutic (treat, augment, repair, or replace a tissue function of the body) or a diagnostic one.
Experts say a number of tissues can potentially be retrieved and stored for use. The Transplantation of Human Organs (Amendment) Act, 2011, includes the component of tissue donation and registration of tissue banks as well.
Biomaterials that can be potentially retrieved and stored –
- Skin: It is used as a biological dressing, in cases of major burns. It helps prevent infections and does not need to be changed every day – it can be kept for a couple of weeks, giving the patient time to recover.
- Bones: Bones from limbs can be stored and used to replace parts that are damaged or diseased. Bone grafts from banks act as scaffolds for support. They could be used in cases of trauma where there is bone loss, in sports injuries, and in cancer cases where parts of the bone and joint cartilage die. The upper end of the shin bone, the lower end of the thigh bone, and the head of the thigh bone can be retrieved for use.
- Ligaments and tendons: These can be used in cases of sports injuries involving multiple ligaments. In some cases, it is difficult to use the patient’s own. The Achilles tendon (ankle), the Peroneal tendon (leg to ankle), the Patellar tendon (front of the knee), and the Meniscus (a shock absorber between the thigh bone and leg bone) can be procured for storage.
- Bone products: Bone powder is made by crushing bones, generally those that would otherwise be disposed of – such as those parts replaced during hip replacement surgeries. These are used to treat various kinds of defects – in dentistry, skeletal and joint reconstruction procedures.
- Amniotic membrane: This is the wall of the amniotic sac. When a baby is delivered, the sac ruptures. The sac can be used as a biological dressing for burns, bedsores, diabetic ulcers, and skin reactions to radiation.
- Heart valves: Heart valves can be retrieved and stored to be used in valve replacement procedures. The advantage with such valves is that the patient does not need blood thinners. They are also cheaper than artificial valves. However, they last about 15 years, and another procedure may be subsequently required. Even in cases where the heart can’t be used, the valve can be retrieved for storage. Usually, the aortic valve is procured.
- Corneas: Corneal transplants are used in cases when the cornea becomes opaque – due to injuries, infections, birth defects, or rarely after surgeries.
Although E. coli is known to the general population for the infectious nature of one particular strain (0157:H7) few people are aware of how versatile and useful E. coli is to genetic research.
The E. coli genome was the first to be completely sequenced (in 1997). E. coli is the well understood bacterium in the world, and is an extremely important model organism in many fields of research, particularly molecular biology, genetics, and biochemistry.
It is easy to grow under laboratory conditions, and research strains are very safe to work with. As with many bacteria, E. coli grows quickly, this allows many generations to be studied in a short time. In fact, under ideal conditions, E. coli cells can double in number after only 20 minutes.
Luciferase is a generic term for the class of oxidative enzymes that produce bioluminescence and is usually distinguished from a photoprotein.
- Luciferases are widely used in biotechnology, for microscopy, and as reporter genes, for many of the same applications as fluorescent proteins. However, unlike fluorescent proteins, luciferases do not require an external light source but do require the addition of luciferin, the consumable substrate.
- Luciferases can be produced in the lab through genetic engineering for a number of purposes. Luciferase genes can be synthesized and inserted into organisms or transfected into cells. Mice, silkworms, and potatoes are just a few of the organisms that have already been engineered to produce the protein.
- In the luciferase reaction, light is emitted when luciferase acts on the appropriate luciferin substrate. Photon emission can be detected by light-sensitive apparatus such as a luminometer or modified optical microscopes.
- In order to generate recombinant DNA molecules, we not only require the vector and insert DNA but also a method to precisely cut these DNA molecules and then join them together (ligation).
- The foundations of rDNA technology were laid by the discovery of restriction enzymes. They are also called as ‘Molecular Scissors’.
- These enzymes exist in many bacteria where they function as a part of a defense mechanism called the Restriction-Modification System.
- A restriction enzyme that selectively recognizes a specific DNA sequence and digests any DNA fragment containing that sequence.
- The term restriction is derived from the ability of these enzymes to restrict the propagation of foreign DNA (e.g. Viral/phage DNA) in a bacterium.
- The Restriction-Modification enzyme system within a given bacterium protects its DNA from digestion by methylation but can digest foreign DNA which is not protected by similar methylation.
- Different species of bacteria contain their own sets of restriction endonucleases and corresponding methylases.
- Three main classes of restriction endonucleases- type I, type II, and type III are present, of which, only type II restriction enzymes are used in rDNA technology.
Antibody, also called immunoglobulin, a protective protein produced by the immune system in response to the presence of a foreign substance, called an antigen. Antibodies recognize and latch onto antigens in order to remove them from the body. A wide range of substances are regarded by the body as antigens, including disease-causing organisms and toxic materials such as insect venom.
When an alien substance enters the body, the immune system is able to recognize it as foreign because molecules on the surface of the antigen differ from those found in the body. To eliminate the invader, the immune system calls on a number of mechanisms, including one of the most important—antibody production.
Antibodies are produced by specialized white blood cells called B lymphocytes (or B cells). When an antigen binds to the B-cell surface, it stimulates the B cell to divide and mature into a group of identical cells called a clone. The mature B cells, called plasma cells, secrete millions of antibodies into the bloodstream and lymphatic system.
Active immunity results when exposure to a disease organism triggers the immune system to produce antibodies to that disease. Exposure to the disease organism can occur through infection with the actual disease (resulting in natural immunity), or introduction of a killed or weakened form of the disease organism through vaccination (vaccine-induced immunity).
Passive immunity is provided when a person is given antibodies to a disease rather than producing them through his or her own immune system. A newborn baby acquires passive immunity from its mother through the placenta.
When antibodies are directly given to protect the body against foreign agents, it is called passive immunity for example foetus receives antibodies from their mother, through the placenta during pregnancy, the yellowish fluid colostrum secreted by mother during the initial days of lactation has abundant antibodies (IgA) to protect the infant.
Active immunity is slow and takes time to give its full effective response whereas passive immunity immediately gives an effective response. Passive immunity lasts for few days or a shorter duration whereas active immunity lasts for a sufficiently longer period or may be lifelong.
Photodynamic therapy uses a photosensitive drug that becomes active under the action of light and converts molecular oxygen into reactive oxygen species that kill cancer cells.
It uses special drugs, called photosensitizing agents, along with light to kill cancer cells. Depending on the part of the body being treated, the photosensitizing agent is either put into the bloodstream through a vein or put on the skin. Over a certain amount of time, the drug is absorbed by the cancer cells. Then light is applied to the area to be treated. The light causes the drug to react with oxygen, which forms a chemical that kills the cells. PDT might also help by destroying the blood vessels that feed the cancer cells and by alerting the immune system to attack cancer.
- Bacteriophages are viruses that infect bacterial cells by injecting their DNA into them and consequently take over the machinery of the bacterial cells to multiply themselves.
- The injected DNA hence is selectively replicated and expressed in the host bacterial cell resulting in a number of phages that eventually extrude out of the cell (lytic pathway) and infect neighboring cells.
- Some phages can only reproduce via a lytic lifecycle, in which they burst and kill their host cells.
- This ability to transfer DNA from the phage genome to specific bacterial hosts during the process of viral infection gave scientists the idea that specifically designed phage-based vectors would be useful tools for gene cloning experiments.
- Two phages that have been extensively modified for the development of cloning vectors are lambda (ë) and M13 phages.
CHARGE syndrome is a rare birth defect that affects approximately 1 in 20,000 people around the world. CHARGE syndrome causes multiple life-threatening problems in a newborn, such as facial bone and nerve defects that cause breathing and swallowing difficulties, deafness and blindness, heart defects, genital problems and growth retardation.
The children may survive and go on to live with these deficiencies if the heart and bone defects are corrected with multiple surgeries, but those without access to such support usually do not survive past their first year.
CHARGE syndrome is a result of defective embryonic development. Two-thirds of the patients with CHARGE syndrome have a sporadic mutation in the gene called CHD7.
Bionics is not a specialized science. It refers to the use of principles of biology to engineering. Now it is used more to describe a method to engineer organs that can replace diseased or non-functional organs in human body.
Bionics is different from bioengineering (or Biotechnology), which is the use of living things to perform industrial tasks like use of microbes to remove waste etc.
The word autophagy is derived from Greek words “auto” meaning self and “phagy” meaning eating. Autophagy is a normal physiological process in the body that deals with destruction of cells in the body.
It maintains homeostasis or normal functioning by protein degradation and turnover of the destroyed cell organelles for new cell formation.
During cellular stress the process of Autophagy is upscaled and increased. Cellular stress is caused when there is deprivation of nutrients and/or growth factors.
Thus Autophagy may provide an alternate source of intracellular building blocks and substrates that may generate energy to enable continuous cell survival.
Autophagy also kills the cells under certain conditions. These are form of programmed cell death (PCD) and are called autophagic cell death. Programmed cell death is commonly termed apoptosis.
Autophagy is termed a nonapoptotic programmed cell death with different pathways and mediators from apoptosis.
Autophagy mainly maintains a balance between the manufacture of cellular components and breakdown of damaged or unnecessary organelles and other cellular constituents.
Thanks to Ohsumi and others following in his footsteps, we now know that autophagy controls important physiological functions where cellular components need to be degraded and recycled.
- Autophagy can rapidly provide fuel for energy and building blocks for the renewal of cellular components and is therefore essential for the cellular response to starvation and other types of stress.
- After infection, autophagy can eliminate invading intracellular bacteria and viruses. Autophagy contributes to embryo development and cell differentiation.
- Cells also use autophagy to eliminate damaged proteins and organelles, a quality control mechanism that is critical for counteracting the negative consequences of aging.
- Disrupted autophagy has been linked to Parkinson’s disease, type 2 diabetes, and other disorders that appear in the elderly. Mutations in autophagy genes can cause genetic disease. Disturbances in the autophagic machinery have also been linked to cancer. Intense research is now ongoing to develop drugs that can target autophagy in various diseases.
- Autophagy has been known for over 50 years but its fundamental importance in physiology and medicine was only recognized after Yoshinori Ohsumi’s paradigm-shifting research in the 1990s. For his discoveries, he is awarded the 2016 Nobel Prize in physiology or medicine.
TRIPLE DRUG THERAPY
The World Health Organization (WHO) is recommending an alternative three-drug treatment to accelerate the global elimination of lymphatic filariasis – a disabling and disfiguring neglected tropical disease.
- The treatment, known as IDA, involves a combination of ivermectin, diethylcarbamazine citrate, and albendazole. It is being recommended annually in settings where its use is expected to have the greatest impact.
- Lymphatic filariasis is caused by infection with parasitic worms living in the lymphatic system. The larval stages of the parasite (microfilaria) circulate in the blood and are transmitted from person to person by mosquitoes.
- The manifestation of the disease after infection takes time and can result in an altered lymphatic system, causing abnormal enlargement of body parts, and leading to severe disability and social stigmatization of those affected.
- The parasites are transmitted by four main types of mosquitoes: Culex, Mansonia, Anopheles, and Aedes.
- A day-long National Symposium on the theme ‘United to Eliminate Lymphatic Filariasis’ was inaugurated by Union Minister for Health and Family Welfare.
- The Union Minister also signed the ‘Call to Action to eliminate Lymphatic Filariasis by 2021’.
- India is set to scale-up the use of Triple Drug Therapy (IDA) in a phased manner starting from November 2019.
Achievements of Biotechnology
- Use of organic material to produce biodegradable plastics, fuel, and fertilizer
- Use of recombinant growth hormone to increase milk and milk production
- In-vitro fertilization of farm animals using selected sperms and eggs.
- Marine Biotechnology
- Fish Farming
- Seaweed farming to produce fatty acids etc
- Production of adhesive from mussels and barnacles
- Recombinant vaccines against Hepatitis B and AIDS
- Drugs such as insulin, eythroprotein.
- Environmental Biotechnology
- Water treatment
- Treatment of air pollution
- Use of plants to remove contamination by heavy materials
- Pollution fighting using enzymes or microbes
- Production of wood pulp for the paper industry
- Production of tree clones from tissue culture
- Other applications
- Production of energy from biomass
- Biological sensors and switches for electronic process