Genetic Engineering

• What's Genetic Engineering


  Involves taking a piece of DNA (usually a gene) from one organism & inserting it into another organisms genetic material (donor->recipient)
• Why are bacteria used in genetic engineering

  1. Bacteria easily manipulated
  2. Bacteria reproduce rapidly producing large numbers quickly with the new gene. Done in best growing conditions (fermenters maximise production)
  3. Bacteria will produce the new gene product which is difficult or expensive to produce by other means
  4. Large quantities of insulin produced
  5. No allergic reaction/harm to animal
• How do you produce human insulin

  1. Select human insulin gene
  2. Cut insulin gene out of chromosome with restriction enzymes
  3. Remove plasmid from bacterial plasmid with same restriction enzymes
  4. Stick DNA into plasmid with ligase enzyme
  5. Plasmid is put back into bacteria
  6. Bacteria grown in fermenters providing best conditions for growth
  7. Bacteria reproduces millions of genes with insulin
• Describe the role of restriction enzymes in genetic engineering

  • Cut DNA at specific sections
  • Leave complimentary sections of exposed bases in both plasmid and gene allows them to join (complimentary pairing)
  • Exposed ends called Sticky Ends
• What are the Downstreaming processes

  1. Extraction from fermenter
  2. Purification
  3. Packaging for medical use
• What are the advantages og genetic engineering compared to older extraction methods

  • Larger quantities can be made
  • Faster and less risk of transferring disease
  • Reduces ethical issues about killing
  • Animal insulin isn't as effective as human insulin