Biotechnology Applications – Study Notes for NEET (Medical)
Biotechnology is the use of living organisms or their components to create useful products.
In medicine it is the engine of modern diagnostics, therapeutics and preventive strategies.
1. Simple Explanation
| Concept | What it means? | Why it matters? |
|---|---|---|
| Biotechnology | Engineering of biological systems to develop products or processes. | Enables rapid drug production, targeted therapies, and disease‑diagnostic tools. |
| Recombinant DNA (rDNA) technology | Cutting a DNA fragment and inserting it into a vector (plasmid/virus). | Produces proteins (insulin, growth hormone) that are otherwise difficult to obtain. |
| PCR (Polymerase Chain Reaction) | Amplifies a specific DNA sequence exponentially using primers and heat‑stable polymerase. | Detects pathogens, genetic mutations, and forensic evidence. |
| Gene therapy | Delivery of functional genes to replace defective ones in patients. | Treats monogenic disorders (e.g., cystic fibrosis, β‑thalassemia). |
| CRISPR‑Cas9 | Programmable DNA‑cutting system derived from bacterial immunity. | Precise genome editing for research & therapeutic purposes. |
| Stem‑cell therapy | Using pluripotent or adult stem cells to regenerate tissue. | Potential cure for spinal cord injury, diabetes, heart disease. |
| Monoclonal antibodies (mAbs) | Identical antibodies from a single B‑cell clone. | Targeted cancer therapies, autoimmune disease treatment. |
| Vaccines (recombinant, subunit, DNA) | Engineered to express specific antigens. | Safer, more effective vaccines (HPV, Hepatitis B). |
| Bioremediation | Using microbes to degrade pollutants. | Environmental cleanup – oil spills, heavy metals. |
| Industrial bioprocesses | Enzymes, bio‑fuels, biodegradable plastics. | Sustainable alternatives to petrochemicals. |
2. Key Points (NEET Focus)
| Area | Important Details |
|---|---|
| Gene‑Editing & Gene Therapy | • Vectors: Adeno‑associated virus (AAV), lentivirus, plasmid. • Clinical examples: Luxturna (Leber’s congenital amaurosis), Zolgensma (Spinal Muscular Atrophy). • Ethical issues: Germline editing, off‑target effects. |
| PCR & Molecular Diagnostics | • Three stages: Denaturation (95 °C), Annealing (~55 °C), Extension (72 °C). • Applications: Detect TB (MTB), COVID‑19, BRCA mutations, paternity testing. |
| Recombinant Protein Production | • Expression systems: Bacterial (E. coli), yeast, insect, mammalian. • Purification: Ni‑NTA affinity (His‑tag), ion‑exchange, gel filtration. • Common drugs: Humulin (human insulin), EPO, interferon‑α. |
| Monoclonal Antibodies | • Hybridoma technique: Fusion of myeloma + B‑cell. • Therapeutics: Rituximab (CD20), Trastuzumab (HER‑2), Pembrolizumab (PD‑1). |
| Stem‑Cell Therapies | • Types: Hematopoietic (bone marrow transplant), Mesenchymal, Induced pluripotent stem cells. • Applications: Treat leukemia, Parkinson’s, myocardial infarction. |
| Vaccines | • Recombinant subunit (HBV, HPV). • DNA vaccines: plasmid encoding antigen, delivered intramuscularly. • mRNA vaccines: lipid‑nanoparticle delivery – COVID‑19. |
| Industrial Biotechnology | • Enzymes: amylases, lipases, cellulases. • Biofuels: Ethanol from starch, biodiesel from algae. • Bioplastics: Polylactic acid (PLA). |
| Bioremediation | • Microbial degradation of hydrocarbons, nitrates, heavy metals. • Biopesticides: Bacillus thuringiensis (Bt) toxin. |
| Ethical & Regulatory Aspects | • Gene therapy: FDA approval, informed consent, post‑marketing surveillance. • Stem‑cell research: Embryonic vs. induced pluripotent. |
3. Worked Example
Case Study: PCR for detection of Mycobacterium tuberculosis (MTB) – GeneXpert® (real‑time PCR)
| Step | Procedure | Key Points |
|---|---|---|
| 1. Sample collection | Sputum sample (≥5 ml). | Use sputum induction if patient is non‑productive. |
| 2. Sample processing | Add 10 % NaOH + 10 % NALC, neutralise, centrifuge. | Decontaminates & concentrates bacilli. |
| 3. DNA extraction | Use silica membrane kit – lysis, binding, wash, elution. | Ensures purity; removes inhibitors. |
| 4. PCR amplification | • Denaturation 95 °C 1 min • Annealing 58 °C 30 s • Extension 72 °C 1 min (30 cycles) |
Use primers for IS6110 region |