GENBIO

• DNA Recombinant Technology

  Altering genetic material outside an organism to obtain enhanced and desired characteristics in living organisms or as their products

  
• Genetic engineering may involve adding a gene from one species to an organism from a different species to produce a desired trait
• Genetic engineering has been applied to the production of cancer therapies, brewing yeasts, genetically modified plants and livestock, and more

  
• Positive Effects of Genetic Engineering

  • Improvement of health
  • Theoretically eliminate the passing of "disease" genes
• Recombinant DNA technology has proven important to the production of vaccines and protein therapies such as human insulin, interferon and human growth hormone

  
• Recombinant DNA technology is used to produce clotting factors for treating hemophilia and in the development of gene therapy

  
• Restriction enzyme EcoRI


  Cleaves the DNA between G and A in a base sequence GAATTC
• Enzymes used in recombinant DNA technology

  • DNA ligase
  • Reverse transcriptase
  • Restriction endonuclease
  • Terminal transcriptase
  • Nuclease
  • DNA polymerase
  • Ribonuclease-H
  • Alkaline phosphatase
  • Polynucleotide kinase
• DNA ligase


  Joins two DNA fragments with cloning vector

  
• Reverse transcriptase


  Synthesizes complementary strand (cDNA) from mRNA template

  
• Restriction endonuclease


  Recognizes and cuts DNA strand at specific sequence called restriction site

  
• Types of restriction endonuclease

  • Type I: Has both methylation and endonuclease activity, requires ATP to cut DNA, cuts DNA about 1000bp away from restriction site
  • Type II: Does not require ATP to cut DNA, cuts DNA at restriction site itself
  • Type III: Requires ATP to cut DNA, cuts DNA about 25bp away from restriction site
• Terminal transferase


  Synthesizes short sequence of complementary nucleotide at free ends of DNA, so that blunt end is converted into sticky end

  
• Nuclease


  Fills the gap with DNA polymerase and strand is joined by DNA ligase

  
• DNA polymerase


  Synthesizes nucleotide complementary to template strand

  
• Ribonuclease-H (RNase H)


  Removes mRNA from DNA-RNA heteroduplex and that mRNA is used to synthesize cDNA
• Alkaline phosphatase


  Helps in removal of terminal phosphate group from 5′ end, prevents self annealing of vector DNA
• Polynucleotide kinase


  Adds phosphate group from ATP molecule to terminal 5'end after dephosphorylation by alkaline phosphatase
• DNA Fingerprinting Techniques


  1. PCR amplification

  2. Restriction Digestion

  3. Gel Electrophoresis

  4. Visualization

  5. Analysis
• Purpose of recombinant DNA technology in insulin production

  To engineer organisms to produce human insulin
• Primary goal of developing genetically modified crops

  Reducing pesticide use, Herbicide resistance
• Organisms commonly used to produce recombinant proteins for medical purposes

  • Escherichia coli (E. coli)
  • Yeast (Saccharomyces cerevisiae)
  • Mammalian Cells

  
• Natural Selection


  • Variation in traits
  • Differential reproduction
  • Heredity
• The more advantageous trait, brown coloration, which allows the beetle to have more offspring, becomes more common in the population</b>
• Artificial Selection


  An evolutionary process in which humans consciously select for or against particular features in organisms
• Artificial Selection


  • Cauliflower, broccoli, cabbage, kale, and kohlrabi evolved from a wild, weedy ancestor
• Genetic Drift


  A mechanism of evolution, the effect of change, can lead to changes in a population's allele frequency
• Genetic Drift


  • Bottleneck, Founder effect
• Mutation


  • Contributes to the genetic diversity within a population, the only evolutionary mechanism that introduces entirely new alleles into a population's gene pool
• Recombination


  A process by which pieces of DNA are broken and recombined to produce new combinations of alleles

  
• Basic Mechanisms of Evolution

  • Natural Selection
  • Mutation
  • Genetic Drift
  • Recombination
  • Gene Flow
• Genetic diversity


  Diversity within a population
• Mutation


  The only evolutionary mechanism that introduces entirely new alleles into a population's gene pool
• Evolution and Origin of Biodiversity: History of Life on Earth and Mechanism of Evolution
• Basic mechanism of evolution

  • Natural selection
  • Mutation
  • Genetic drift
  • Recombination
  • Gene flow
• Natural selection


  A simple mechanism that causes populations of living things to change over time
• Mutation


  Can change one allele into another, but the net effect is change in frequency
• Genetic drift


  Can be magnified by natural or human-caused events, such as disaster that randomly kills a large portion of population, which is known as the bottleneck effect resulting in a large portion of genome suddenly being wiped out
• Gene flow


  The flow of alleles in and out of the population resulting from the migration of individuals or gametes
• Recombination


  Occurs during meiosis when chromosomes exchange genes