Genetic Engineering and Biotechnology: Applications and Impacts

Genetic Engineering: Understanding the Building Blocks

Genetic engineering relies on our knowledge of the genetic code, gene regulation mechanisms, transcription, translation, and reduction. Automated sequencing techniques, restriction enzymes, and a set of other tools allow us to split and join DNA fragments. These fragments, when combined with other macromolecular carrier DNA, enable the transfer of genetic information between organisms. These are called recombinant DNA molecules.

Key Processes in Genetic Engineering

• DNA Transformation: A cell undergoes a genetic change resulting from the entry of a foreign DNA molecule into its core.
• Transduction: The process of transferring genetic information (e.g., in bacteria) without direct contact, often mediated by a bacteriophage virus.

Once transferred and assembled with another DNA molecule that acts as a carrier, the DNA can replicate and express itself. This process is called cloning. Plasmids and viruses are commonly used as DNA cloning vectors.

Biotechnology Applications

1. Food Industry

Biotechnology plays a crucial role in the production of various food products, such as dairy products (yogurt, cheese, etc.), vinegar, bakery products, pastries, and beverages (wine, beer, etc.). These manufacturing processes often rely on fermentation. Introducing genetically modified microorganisms can improve these processes.

2. Pharmaceuticals

• Antibiotic Production: Substances produced by fungi and bacteria.
• Vitamins: Some are obtained through chemical synthesis, while others are produced by microorganism cultures.
• Other Important Molecules: Insulin, hemoglobin, blood coagulation factors, growth hormone, and protein-rich vaccines can be produced by transferring human genes to bacteria. These bacteria are then grown in industrial devices called bioreactors.

3. Agriculture and Livestock (Transgenic Foods)

Plants can be genetically modified to incorporate genes from other organisms, conferring resistance to herbicides, insect pests, viruses, etc. Three primary methods are used for genetic transformation:

• Agrobacterium tumefaciens-mediated transformation: This bacterium naturally produces tumors by transferring its genes.
• Electroporation: Opening membrane pores to allow DNA entry.
• Biolistics: Bombardment with a particle accelerator carrying DNA.

Biological control methods, such as using insect predators or sterile insects obtained through ionizing radiation, are also employed. Transgenic animals can be created by introducing genes into zygotes, which are then implanted to track their development. For example, transgenic mice can be created by introducing the growth hormone gene. Other examples include"ni" genes that enable nitrogen utilization and transgenic maize varieties that resist frost due to the incorporation of a cold-resistant fish gene.

4. Medical Applications

• Tissue Engineering: Cultivation of stem cells to generate different tissue types.
• Forensics: Identification of individuals, paternity testing, and diagnosis of genetic diseases in humans or fetuses.
• Gene Therapy: Removal of a defective gene and its replacement with a desired gene.
• Human Genome Project (HGP): Launched in 1988, the HGP aimed to sequence the entire DNA of human cells. Early results indicated that the human genome contains approximately 3 billion base pairs. This data is being used to locate genes, understand gene variations, determine when and where genes are activated, and study protein activity and its relationship to diseases.
• Cancer Research: The transformation of a normal cell into a cancerous one is often linked to environmental factors that alter DNA. Several genes (proto-oncogenes) are believed to undergo transformation and cause cancer. Examples of these factors include viruses, radiation, and certain chemical substances.

5. Environmental Applications

Biotechnology can be used for wastewater treatment in bioreactors, where microbial silt produces biogas that can be used as fuel. Certain bacteria can also be used to remove oil spills.

Ethical Considerations

The production of transgenic organisms raises concerns about potential environmental and health risks. There are also moral and ethical debates surrounding gene manipulation, even with the intention of curing diseases. Social concerns include the requirement of genetic probes for employment and insurance purposes. There is also controversy surrounding the patenting of the human genome sequence.