21.5 Gene technology and ethics

• Suggest a reason for genetically modifying a plant.

  Insect resistance, drought tolerance, pesticide resistance, faster growth, better flavour, slower ripening etc.
• State a negative aspect of genetically modifying plants.

  Create monocultures (susceptible to extinction), chance of gene transfer to create superweeds, expensive to buy
• What is 'pharming'?

  Making medicinal drugs (pharmaceuticals) from genetically modified organisms
• Give an ethical positive and negative to “pharming”.

  Positive– easier/cheaper production of medicine

  Negative – long term effects to health of organism unknown, patenting issues
• Give a positive and negative ethical issue of genetically engineering pathogens

  Positive - may be able to engineer them to attack cancer cells

  Negative - Risk of mutation/reversion and therefore cause major outbreak of disease, intentional biowarfare
• What is gene therapy?

  Altering alleles to treat genetic diseases
• What’s the difference between somatic cell therapy and germ line cell therapy?

  Somatic - altering genes in body cells

  Germ Line – altering genes in gametes or zygote
• State a negative feature of somatic cell gene therapy.

  Effects are often short-lived, multiple treatments may be needed, hard to target some body cells, allele could go to wrong place and cause a problem, expensive, where do we draw the line? (e.g. should we 'fix' short-sightedness, baldness, hair colour etc.)
• State a negative feature of germline gene therapy.

  Offspring will also carry altered genes - may be unknown long term effects
• Why is it harder to treat genetic disorders caused by dominant alleles than disorders caused by recessive alleles?

  Recessive allele treatment just needs addition of the "correct" allele anywhere in genome. Treatment of a dominant condition requires that specific gene to be disrupted/silenced. This requires more specific placement of inserted DNA
• State whether each type of gene therapy (somatic and germline) is legal or illegal.

  Somatic = legal

  Germline = illegal