Revision: Biotechnology Biology HSC Science (General) 12th Standard Board Exam Maharashtra State Board

The technique of bringing about improvements in living organisms by genetic modifications and hybridization, for the welfare of human beings is known as ‘Biotechnology’.

The European Federation of Biotechnology (EFB) defined biotechnology as ‘the integration of natural science and organisms, cells, parts thereof, and molecular analogues for products and services.’

A genomic library is a collection of clones that represent an organism's whole genome.

The technique of treating genetic disorders by correcting defective genes in somatic cells is called gene therapy.

A transgenic animal is an animal whose genome has been artificially modified to contain one or more genes from another species.

Bioethics is the branch of ethics that deals with moral principles and issues arising from advances in biology, medicine, and life sciences.

Bioethics are a set of standards that may be used to regulate our activities in relation to the biological world.

Patents granted for biological entities and for products derived from them are called biopatents.

Biopiracy is defined as ‘theft of various natural products and then selling them by getting patent without giving any benefits or compensation back to the host country’.

or

It is an unauthorised misappropriation of any biological resource and indigenous knowledge.

• Biotechnology is the use of biological systems, cells, and organisms to develop useful products and services for human welfare.
• The term biotechnology was coined by Karl Ereky (1919).
• Traditional biotechnology involves small-scale processes like fermentation (e.g., curd, cheese, wine), while modern biotechnology is large-scale and based on genetic engineering.
• Modern biotechnology was advanced by recombinant DNA (rDNA) technology developed by Cohen and Boyer (1973).
• It involves techniques like gene modification, PCR, and tissue culture, and integrates fields like molecular biology and genetics.
• Biotechnology has wide applications in agriculture and medicine, such as the production of antibiotics, vaccines, insulin, and the development of high-yield and disease-resistant crops.

• Two Core Techniques — Modern biotechnology is based on (i) Genetic Engineering and (ii) Chemical Engineering.
• Genetic Engineering — Deals with the alteration of DNA and RNA to achieve desired results in a directed, predetermined way using in vitro processes.
• Chemical Engineering — Maintains a sterile environment for manufacturing useful products like vaccines, antibodies, enzymes, vitamins, and therapeutics.
• What Genetic Engineering Involves — Repairing/replacing defective genes, synthesising new genes, transferring genes, combining genes from two organisms, and altering genotype.
• Other Names for Genetic Engineering — Also called Recombinant DNA (rDNA) Technology or Gene Cloning, as it involves transferring a gene via a suitable vector to a new location or organism.

• Gene cloning is the process of transferring a gene of interest into a host cell using a vector, where it replicates and passes to progeny.
• Important tools include instruments like electrophoresis (for separation) and PCR (for amplification of DNA).
• PCR (Polymerase Chain Reaction) amplifies DNA through three steps: denaturation, annealing, and extension, producing many copies of the desired gene.
• Restriction enzymes act as molecular scissors, cutting DNA at specific recognition (palindromic) sequences to form sticky or blunt ends.
• Cloning vectors (like plasmids and bacteriophages) carry foreign DNA into host cells and allow its replication.
• A good vector must have features like origin of replication, marker genes, and restriction sites for effective cloning.
• Competent host cells (commonly E. coli) are used to take up recombinant DNA and produce the desired gene product.

• The first step is isolation of DNA from the donor organism and cutting it into fragments using restriction enzymes.
• The desired gene (foreign DNA) is selected and inserted into a cloning vector (like a plasmid) using DNA ligase to form recombinant DNA.
• The recombinant DNA is transferred into a competent host cell (e.g., E. coli) by transformation or other methods like electroporation.
• Transformed cells are identified using marker genes (e.g., antibiotic resistance) to distinguish them from non-transformed cells.
• Selected transformed cells are multiplied in culture, leading to replication of recombinant DNA.
• The inserted gene is expressed to produce the desired product, such as enzymes, hormones, or antibiotics.
• Finally, the product is extracted and purified through downstream processing for use.

• Earlier insulin was obtained from animals, which caused allergic reactions and could not meet large-scale demand.
• Recombinant DNA technology enabled large-scale production of human insulin, first produced in 1983 as Humulin®.
• Human insulin consists of two polypeptide chains (A and B) that are produced separately in E. coli using plasmid vectors.
• The purified A and B chains are joined by disulphide bonds to form active human insulin.

• Biotechnology has wide applications in healthcare, agriculture, industry, the environment, and genomics.
• In healthcare, it provides diagnostic and therapeutic solutions such as stem cell therapy, genetic counselling, DNA fingerprinting, and gene probes.
• Human insulin is produced using recombinant DNA technology by inserting insulin genes into bacteria like E. coli.
• Biotechnology helps in the production of vaccines using weakened or modified microorganisms to provide immunity against diseases.
• Advanced vaccines include recombinant vaccines, DNA vaccines, and plant-based (edible) vaccines.
• Oral and “melt-in-the-mouth” vaccines are modern innovations that are easy to administer and cost-effective.
• Biotechnology has significantly helped in controlling diseases like smallpox and polio and is advancing towards treating major diseases like cancer.

• Vaccines produced using recombinant DNA technology are called recombinant or subunit vaccines, such as the hepatitis-B vaccine.
• These vaccines may be protein vaccines (using specific antigens) or DNA vaccines that induce an immune response.
• Examples include hepatitis-B vaccine produced in yeast, rotavirus, dengue, HPV vaccines, and plant-based edible vaccines.

• Biotechnology in agriculture involves the use of genetically modified (GM) crops to improve productivity, pest resistance, and stress tolerance.
• Tissue culture is used for micropropagation, allowing rapid and large-scale production of identical plants (clones).
• It is also useful for germplasm conservation and for plants with recalcitrant seeds that are difficult to store.
• To increase food production, three approaches are used: agrochemical-based, organic, and genetically engineered crop-based agriculture.
• Genetic engineering helps overcome the limitations of traditional methods and reduces dependence on expensive and polluting agrochemicals.

• Gene therapy is the treatment of diseases by replacing, altering, or adding genes to correct genetic defects.
• It is used to treat genetic disorders such as haemophilia, cystic fibrosis, sickle cell anaemia, and thalassemia.
• Genes can be delivered into cells by ex vivo (outside the body), in vivo (inside the body), or using vectors like viruses and liposomes.
• There are two types: germ-line therapy (affects future generations, not used in humans) and somatic cell therapy (affects only the patient and is commonly used).
• Gene therapy has applications in treating genetic diseases, cancer, and improving immune response, but it involves technical and ethical challenges.

• Bioethics is the study of moral principles and decisions related to biological sciences and their impact on society.
• It deals with issues like cloning, gene therapy, genetic engineering, euthanasia, and in vitro fertilisation.
• Biotechnology raises ethical concerns such as animal suffering, gene transfer between species, and misuse of living organisms.
• Genetically modified organisms (GMOs) may pose risks to human health, the environment, and biodiversity, and can disturb natural processes.
• To ensure safety and ethical use, measures like biosafety regulations and organisations such as the Genetic Engineering Approval Committee (GEAC) are established.

• Genetically modified (GM) crops may increase herbicide use, leading to harmful environmental effects.
• Weeds and nearby plants can develop herbicide resistance through cross-pollination, reducing the effectiveness of chemicals.
• GM crops like Bt corn produce their own pesticides, which can harm non-target organisms.
• Beneficial species, such as insects (e.g., butterflies), may be adversely affected by these genetically modified crops.
• Thus, biotechnology in agriculture requires careful regulation to avoid ecological imbalance.

• Genetically modified (GM) foods may cause allergic reactions, as seen in cases like soybean modified with Brazil nut genes.
• The long-term health effects of GMOs are not fully known due to limited research.
• Introduction of new proteins in GM foods may have unknown effects on the human body.
• Biotechnology can improve nutrition and health by adding nutrients, vaccines, and antibiotics to food, but it may also lead to resistant pathogens.
• To ensure safety, regulatory bodies like the Genetic Engineering Approval Committee (GEAC) monitor and control the use of GMOs.

• A biopatent is a legal right granted for biological inventions such as microorganisms, DNA sequences, genetically modified organisms, and biotechnological processes.
• A patent gives the inventor exclusive rights to use, sell, or distribute the invention for a limited period.
• Biopatents are awarded to encourage innovation and scientific development in biotechnology.
• In India, only process patents are allowed (not product patents), and biopatents are granted for a limited duration.
• Some biopatents (e.g., genetically modified seeds) are controversial as they may lead to a monopoly and threaten food security.

• Biopiracy is the unauthorised use or patenting of biological resources and traditional knowledge without giving compensation to the original owners.
• It mainly occurs when developed countries exploit the rich biodiversity and traditional knowledge of developing countries.
• Traditional knowledge includes information about agriculture, medicines, and conservation practices passed through generations.
• Biopiracy harms indigenous communities by denying them rights, benefits, and recognition for their knowledge.
• Common examples include the patenting of neem, basmati rice, and turmeric (haldi) by foreign companies, which were later challenged and revoked.