GENETIC_ENGINEERING

• The last five to ten years have seen some extraordinary feats in biology, among them determination of the complete DNA sequences of several extinct species, including woolly mammoths, Neanderthals, and a 700,000-year-old horse
• Pivotal to those discoveries was the sequencing of the human genome, essentially completed in 2003. This endeavor marked a turning point in biology because it sparked remarkable technological advances in DNA sequencing

  
• Recombinant DNA


  A technique where DNA molecules when segments of a DNA from two different sources (often different species) are combined in vitro (test tubes)

  
• This advances set the stage for further development of powerful techniques for analyzing genes and gene expression
• Biotechnology


  Technology that utilizes biological systems, living organisms or parts of this to develop or create different products

  
• Biotechnology

  • Brewing
  • Baking bread
• Genetic Engineering

  The direct manipulation of genes for practical purposes
• Gene Cloning

  Preparing well defined segments of DNA in multiple identical copies

  
• Plasmid

  Small circular extra-chromosomal DNA molecules that can replicate separately from its bacterial chromosome

  
• Restriction Enzymes


  Enzymes that cut DNA molecules at a limited number of specific locations

  
• Sticky End


  The restriction enzyme cuts at one end of the sequence, between two bases on the same strand, then cuts on the opposite end of the complementary strand. This will produce two ends of DNA that will have some nucleotides without any complementary bases

  
• DNA Ligase


  DNA joining enzyme
• In DNA cloning, restriction enzymes and DNA ligase are used to insert genes and other pieces of DNA into plasmids

  
• Genetic Engineering


  The direct manipulation of DNA to alter an organism's characteristics (phenotype) in a particular way

  
• Molecular Cloning


  The process of creating multiple identical copies of a gene or other DNA sequence

  
• How Genetic Engineering Works

  1. New DNA is transferred into plant cells

  2. The cells are then grown in tissue culture where they develop into plants

  3. The seeds produced by these plants will inherit the new DNA

  
• Transgenic


  If the foreign DNA that is introduced comes from a different species, the host organism is called transgenic

  
• Genetic Modification on Crops

  • Bt corn (Bacillus thuringensis)

  
• CRISPR Technology


  The new golden child of genetic engineering
• CRISPR Technology


  • C- Clustered
  • R-Regularly
  • I- Interspaced
  • S-Short
  • P-Palindromic
  • R-Repeats
• Practical Applications of DNA Technology

  • Medical Applications
  • Forensic Evidences and Genetic Profile
  • In Vitro Fertilization
  • Environmental Clean Up
  • Agriculture

  
• Medical Applications


  • DNA technology helps us identified or detect mutations of genes responsible for human diseases
  • Can compare gene expression in healthy and disease tissue
  • Researchers hope to find what genes are turned on or off in a particular disease
  • These genes and their products are potential for prevention and therapy
  • Pharmaceutical products development

  
• Forensic Evidences and Genetic Profile

  • DNA testing can help identify the guilty individual towards certain crimes
  • STR Analysis (short tandem repeats)
• In Vitro Fertilization


  • Helps in fertility
  • Prevent genetic diseases and assist child's conception
• Bioremediation


  • Many bacteria can extract heavy metals, such as copper, lead, and nickel, from their environments and incorporate the metals into compounds such as copper sulfate or lead sulfate, which are readily recoverable
  • Genetically engineered microbes may become important in both mining (especially as ore reserves are depleted) and cleaning up highly toxic mining wastes
  • Biotechnologists are also trying to engineer microbes that can degrade chlorinated hydrocarbons and other harmful compounds
• Agriculture


  • Selective breeding of both livestock (animal husbandry) and crops
  • Creation of a transgenic animal are often the same as the goals of traditional breeding
  • Crop plants with genes for desirable traits, such as delayed ripening and resistance to spoilage and disease, as well as drought
• In India, the insertion of a salinity resistance gene from a coastal mangrove plant into the genomes of several rice varieties has resulted in rice plants that can grow in water three times as salty as seawater
• Ethical Concerns/Controversies on DNA Technology/Genetic Engineering

  • Possibility that hazardous new pathogen might be created
  • Possible hazards of GMOs
  • GMOs risk to human health
  • CRISPR's scandal: Gene edited babies
  • Who should have the right to examine someone else's genetic information?
  • How should that information be used? Should a person's genome be a factor in determining eligibility for a job or insurance?

  
• Ethical considerations, as well as concerns about potential environmental and health hazards, will likely slow some applications of biotechnology. There is always a danger that too much regulation will stifle basic research and its potential benefits
• The power of DNA technology and genetic engineering—our ability to profoundly and rapidly alter species that have been evolving for millennia—demands that we proceed with humility and caution