Medical Biotechnology | Zoology Optional Notes for UPSC PDF Download

Historical Background

• 10,000 years ago: Humans domesticated crops and livestock
• 6,000 years ago: Biotechnology used for leavening bread and fermenting beer (Egypt)
• 6,000 years ago: Production of cheese and fermentation of wine (Sumeria, China, and Egypt)
• 2,500 years ago: First antibiotic discovered in China, used to treat boils

Definition of Biotechnology

• Biotechnology combines biological processes with technology to solve problems and create useful products
• Humans have employed natural biological processes for food production and disease treatment for thousands of years

History of Medical Biotechnology

• 1797: Edward Jenner's first vaccination against smallpox
• 1919: First use of the term "biotechnology" in print
• 1928: Discovery of penicillin as an antibiotic by Alexander Fleming
• 1938: Coining of the term "molecular biology"
• 1941: First use of the term "genetic engineering" by Danish microbiologist A. Jost
• 1942: Mass production of penicillin in microbes
• 1944: Isolation of streptomycin, an effective antibiotic for tuberculosis, by Waksman

Medical Biotechnology Aims

• Prevention, diagnosis, and treatment of diseases
• Involves basic research on disease mechanisms and genomic and genetic determinants of diseases

Genomic Complexity

• Only 1% of the human genome is transcribed into mRNA and translated into proteins
• Additional 0.5% serves as a template for noncoding RNA and regulatory regions controlling gene expression
• The remaining 98.5% of the genome, referred to as "dark matter," contains functional conserved noncoding elements

Genetic Nature of Diseases

• Diseases can be monogenic (inherited) or polygenic (acquired)
• Complex diseases result from the cumulative and interactive effects of multiple loci

Tools and Products of Medical Biotechnology

• Prevention, diagnostics at the nucleic acid level, and treatment using recombinant DNA technology, genetic therapy, cell therapy, and biomedical engineering

Prevention Measures

• Primary: Health promotion and immunization
• Secondary: Early disease detection through screening and case finding
• Tertiary: Reversing, arresting, or delaying disease progression and preventing complications of chronic diseases
• Quaternary: Avoiding consequences related to overmedication, overdiagnosis, or incidental findings

Genetic Tests

• Cytogenetic analysis, detection of mutations, PCR technology, and sequencing used for disease diagnosis and risk assessment

BRCA1 and BRCA2 Mutations

• Lifetime risk of breast cancer: BRCA1 mutations (50-80%), BRCA2 mutations (40-70%)
• Risk of ovarian cancer: BRCA1 mutations (40%), BRCA2 mutations (20%)
• Mutations in these genes account for a small percentage of breast and ovarian cancers

Genetic Testing Purposes

• Preimplantation diagnostics after in vitro fertilization
• Prenatal and postnatal diagnostics

Human Genome Project (HGP)

• Completed in 2003, identified genes, determined DNA sequences, and addressed ethical, legal, and social issues
• Project catalyzed the biotechnology industry and fostered medical applications development

Development of Sequencing Technology

• Sequencing of the human genome and other organisms made possible by DNA sequencing technology advancements
• Maxam-Gilbert sequencing method, based on chemical modification of DNA, allowed rapid analysis of sequences

PCR Technology

• PCR technology, developed by Kary Mullis, enables the amplification of specific DNA sequences
• Cycles of DNA denaturation, primer annealing, and extension result in exponential amplification of target DNA

Genetic Testing and Disease Diagnosis

• Genetic testing plays a crucial role in diagnosing diseases and assessing risk
• PCR technology used to detect mutations associated with diseases like cystic fibrosis
• Identification of mutations in genes like BRCA1 and BRCA2 helps assess the risk of hereditary diseases

The Human Genome Project

• Completed in 2003, aimed to identify all human genes and determine DNA sequences
• Addressed ethical, legal, and social issues arising from genomic research
• Catalyzed the growth of the biotechnology industry and facilitated medical applications development