Fun With Genes

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Fun With Genes
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Cloning and Recombinant DNA

• Cloning using DNA of an organism to create exact
  replicas
  
• Recombinant DNA adding or removing portions of
  DNA from an organism to create offspring with
  desired traits
  
• Gene Therapy Modifying DNA of an organism to
  repair defects or create desired changes

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Natural Cloning

• Propagation by runners
• Strawberries
• Hostas
• Identical Twins
• Armadillos
• Fertility drugs often induce artificially

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Artificial Cloning

• Dolly (1997) First organism cloned from adult
• Previously thought adult DNA unsuitable for
  cloning
  
• Dolly died prematurely as if born old
• Numerous technical problems unsolved
• Claims of human cloning undocumented

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Applications of Cloning

• Replication of DNA
• Replication of desirable cells
• Replication of desirable organisms
• Further loss of genetic diversity?
• Potential for preserving diversity?
• Preservation of endangered species and
  restoration of extinct ones
  
• What about habitat?
• How do we restore lost ecological niches?
• Better to focus on conservation?

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Science Fiction Cloning

• Production of replacement organs
• Attack of the Clones
• Identical twins are not mindless robots
• Ordinary humans are perfectly capable of mindless
  obedience
  
• Cloned humans probably would have behavioral
  traits in common
  
• Biggest advantage need stock only one size
  uniform

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Polyploidy

• Creation of multiple copies of genes and
  chromosomes in same cells
  
• Can happen naturally (about half of flowering
  plant species) or be induced artificially
  (colchicine)
  
• Used to enhance reproductive stability of crops,
  reduce impact of mutations

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Recombinant DNA

• Transgenic Organisms
• Further loss of biodiversity in crop plants?
• Terminator Genes
• Possibility of genetic transfer
• Natural Pesticides
• Indiscriminate Spread
• Creation of Resistance
• Transgenic Organisms Banned in California

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Gene Therapy

• Best bet creation of healthy cells (for example
  bone marrow) to replace unhealthy ones
  
• In-situ repair of genes is a long way off (for
  example, removing genes for diabetes)

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Conclusions and Concerns

• Most concern is not directed against what is now
  possible but what might happen in the future
  
• Genetically enhanced individuals have unfair
  advantages?
  
• Potential for discrimination
• Release of genes and organisms into environment
• Potential for bio-terrorism?