Revision: Biotechnology and Its Applications >> Biotechnology and Its Applications Biology (Theory) ISC (Science) ISC Class 12 CISCE

The soil bacterium Bacillus thuringiensis (Bt) produces an insecticidal protein called 'Bt toxin'.

Bt cotton is a transgenic cotton variety that contains one or more genes from Bacillus thuringiensis and therefore produces an insecticidal protein toxic to certain insect pests.

Stem cells are undifferentiated, unspecialised, totipotent cells that can divide indefinitely for self‑renewal and have the potential to differentiate into different types of specialised cells.

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

ELISA is an immunological test based on the antigen–antibody reaction, used to detect and measure antigens or antibodies in biological samples.

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

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

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

'Biopiracy' is defined as 'the theft of various natural products and then selling them by getting a 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.

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

• While the Green Revolution significantly increased food production using agrochemicals, biotechnology offers a sustainable alternative to overcome yield limitations and chemical pollution.
• Tissue culture enables micropropagation, allowing for the rapid, large-scale production of genetically identical and disease-free plants from small tissue samples.
• Somatic hybridisation allows scientists to fuse the cell-wall-free protoplasts of two distinct plant varieties to create new hybrids with combined desirable traits.
• Genetically modified crops are engineered to possess highly beneficial characteristics, including enhanced nutritional value and increased tolerance to harsh environmental stresses.
• Agricultural biotechnology drastically reduces the reliance on harmful chemical pesticides by developing inherently pest-resistant plants, such as Bt cotton.

• Bt cotton is a transgenic cotton crop containing gene(s) from the soil bacterium Bacillus thuringiensis, enabling it to produce an insecticidal protein.
• This protein, known as Bt toxin, is initially produced in an inactive form called a protoxin.
• The protoxin becomes activated only in the alkaline gut environment of susceptible insects such as bollworms.
• The active toxin binds to midgut epithelial cells, causing pore formation, cell swelling, and eventual cell lysis leading to insect death.
• Different cry genes (cryIAc, cryIIAb, and cryIAb) target different pests, with cryIAc and cryIIAb controlling cotton bollworm and cryIAb controlling corn borer.
• Bt cotton reduces dependence on chemical insecticides and offers targeted pest resistance, though insects may eventually develop resistance to the toxin over time.

• Nematode pests like Meloidogyne incognita damage plant roots, reduce crop yield, and require bioengineering for resistance.
• RNA interference (RNAi) is used to silence pest genes by preventing translation of nematode mRNA.
• In transgenic tobacco, both sense and antisense RNA are produced, forming dsRNA that triggers post-transcriptional gene silencing.
• Agrobacterium tumefaciens is used as a vector to transfer nematode-specific genes, making plants pest-resistant.

• Nematode-specific genes are introduced into the host plant using an Agrobacterium vector to synthesise complementary sense and antisense RNA.
• These complementary RNA strands pair together within the host cells to form a double-stranded RNA (dsRNA) molecule.
• Once the nematode ingests the dsRNA, an enzyme called dicer cleaves it into smaller fragments known as small interfering RNAs (siRNA).
• The siRNA binds with the Argonaute protein to form the RNA-induced silencing complex (RISC), where it unwinds into a single active strand.
• This single-stranded siRNA guides the RISC to bind specifically to the complementary target mRNA produced by the nematode.
• The complex cleaves the target mRNA, effectively blocking its translation into protein and neutralising the parasite to protect the plant.

• Recombinant DNA technology allows for the mass production of safe therapeutic proteins, eliminating the allergic reactions associated with earlier animal-derived medicines.
• Genetically engineered human insulin is produced by separately synthesising the A and B chains in E. coli and linking them with disulphide bonds.
• Biotechnology facilitates the development of recombinant subunit vaccines, which use specific pathogen antigens to safely stimulate the immune system.
• Transgenic plants can be engineered to produce cost-effective edible vaccines that deliver injection-free mucosal and systemic immunity upon consumption.
• Gene therapy treats genetic disorders like ADA deficiency (SCID) by using retroviral vectors to insert a functional gene into a patient's extracted lymphocytes.
• Patients receiving gene therapy for ADA deficiency require periodic infusions of genetically corrected lymphocytes because these cells have a limited lifespan.
• Polymerase Chain Reaction (PCR) is a highly sensitive molecular diagnostic tool that amplifies trace amounts of DNA or RNA to detect diseases before clinical symptoms arise.
• Molecular diagnostics also use ELISA for mass screening via antigen-antibody reactions and DNA probes to detect specific genetic mutations through hybridisation.

• Stem cells are unspecialised cells capable of continuous self-renewal and differentiation into various specialised cell types.
• They are utilised in drug development and offer therapeutic solutions for malignant, genetic, and neurodegenerative diseases like Parkinson’s.
• Totipotent stem cells possess the highest differentiation capacity, allowing a single cell to develop into a complete organism.
• Pluripotent cells can differentiate into all cell types, whereas multipotent cells are restricted to closely related families of cells.
• Embryonic stem cells, isolated from human blastocysts, are the most versatile type and hold the highest potential for transplant applications.
• Adult stem cells, commonly sourced from bone marrow, are practically applied to treat specific conditions such as liver cirrhosis and spinal cord injuries.

• Stem cell therapy utilises stem cells as a medical intervention to prevent and manage various diseases.
• Bone-marrow transplantation is currently the most universally accepted and widely practised form of this therapy.
• It is routinely and successfully employed to treat congenital immunodeficiency disorders, such as SCID.
• The therapy is a standard treatment for severe blood-related conditions, including leukaemia, sickle cell anaemia, and thalassaemia.
• It offers significant therapeutic potential for repairing physical trauma, such as brain and spinal cord injuries, as well as general wound healing.
• Emerging applications target a diverse range of conditions, including diabetes, osteoarthritis, Parkinson’s disease, and the restoration of vision and hearing.

• 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 thalassaemia.
• 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.

• Conventional serum and urine analyses are ineffective for early disease detection, making modern molecular methods essential for effective medical treatment.
• Advanced techniques like Polymerase Chain Reaction (PCR), ELISA, and recombinant DNA technology allow for the diagnosis of diseases even before visible symptoms appear.
• PCR facilitates early detection by amplifying the nucleic acids of pathogens, enabling the identification of extremely low concentrations of viruses like HIV.
• PCR is additionally utilised as a highly effective tool to detect specific gene mutations in suspected cancer patients and to diagnose various genetic disorders.
• During autoradiography, a radioactive probe hybridises to complementary DNA; mutations are identified because the probe fails to bind to the mutated sequence, leaving it unobserved on the photographic film.

• ELISA is a simple, highly specific, and sensitive immunological test grounded in the principle of antigen-antibody reactions.
• It is widely utilised to detect and quantify antigens, antibodies, proteins, and glycoproteins within biological samples.
• Infections can be diagnosed by directly identifying the presence of pathogen antigens in a patient's sample.
• Alternatively, diagnoses can be made by detecting the specific antibodies produced against a pathogen in the patient's serum.
• The assay demonstrates high efficiency by enabling the simultaneous measurement of multiple samples in a single experiment without complex sample preparation.

• Transgenic animals have artificially modified genomes containing specific foreign genes from other species.
• They are produced by isolating a desired gene, inserting it into a host embryo, and growing it into a complete animal expressing the new trait.
• They serve as essential living models for studying normal physiology, understanding complex diseases, and testing the safety of vaccines and chemicals.
• They function as biological factories for therapeutic products, such as "Rosie", the first transgenic cow that produced human protein-enriched milk.
• Mice are the most widely used models in disease research, while other animals such as sheep, pigs, and fish are utilised for medical and agricultural advancements.

• A biopatent is a special legal right granted to an inventor that provides exclusive commercial control over a biological entity or its derived products for a specific period.
• These patents specifically cover biological components such as microorganism strains, cell lines, DNA sequences, genetically modified strains, and biotechnological processes.
• A standard patent document is structured into three specific parts: the legal grant, the detailed technical specification, and the specific claims of protection.
• In India, patent laws permit process patents for the methods used to create biological materials but strictly prohibit product patents for the biological materials themselves.
• The first significant biopatent was awarded for an environmentally beneficial, genetically engineered strain of Pseudomonas bacteria capable of degrading oil spills.
• The controversial US patent granted for a rice variety derived from Indian Basmati serves as a major example of biopiracy and the commercial exploitation of traditional resources.
• India actively rejects certain biopatents on ethical and food-security grounds, such as denying terminator gene technology because it would prevent farmers from saving and replanting seeds.

• Established by the Indian government to approve and validate Genetically Modified (GM) products for public use.
• Responsible for testing GM crops and ensuring their use is environmentally safe.
• Holds the authority to approve or reject large-scale GM organism research.
• Strictly regulates the storage, usage, import, and export of hazardous microbes and genetically engineered organisms.

• Bioethics sets moral standards to safely regulate biotechnology and prevent the misuse of biological resources.
• Major ethical concerns focus on preventing animal suffering in research and avoiding the ecological risks of cross-species gene transfer.
• Biosafety protocols are essential to protect human health and the environment from the unpredictable effects of genetically modified organisms (GMOs).
• The Genetic Engineering Appraisal Committee (GEAC) strictly evaluates and regulates the safe release of genetically engineered products into the environment.

• 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.

Traditional Recognition: Society has historically provided informal rewards to inventors, as novel and innovative goods naturally generate higher returns and value.

Need for Formal Protection: In today’s highly globalised society, informal recognition is no longer sufficient; a formal legal system is required to protect an inventor's work.

Significance of Protection: Assuring formal protection for innovations is essential to the following:

• Encourage continuous advancements in science & technology (S&T).
• Promote fair trade practices.
• Foster healthy market competition.

Intellectual Property Rights (IPRs): This is the formal, overarching legal term used for the rights that protect inventors and their scientific innovations or discoveries from unauthorised commercial use.