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11 Cards in this Set
- Front
- Back
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What does gene therapy involve? |
Altering the defective genes (mutated alleles) inside cells to treat genetic disorders and cancer. • involves inserting a DNA fragment into a person’s DNA (just like recombinant DNA tech) • uses a vector to get the DNA into the cell (just like recombinant DNA tech) |
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Exactly how you do gene therapy depends on whether the disorder is caused by a mutated dominant allele or by two mutated recessive alleles. Describe simply how you’d approach each situation? |
Mutated dominant allele: • silence the dominant allele by inserting a DNA fragment into the middle of the allele, so the allele stops working Two mutated recessive alleles: • Add a working dominant allele to make up for them - it’s called to ‘supplement’ the faulty ones |
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Name the two types of gene therapy? |
• Somatic therapy • Germ line therapy |
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What different vectors can be used in gene therapy? |
• Altered viruses • Plasmids • Liposomes (spheres of lipid) |
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What is somatic therapy? (type of gene therapy) |
Involves altering the alleles in body cells (particularly in the cells that are most affected by the disorder) e.g. in cystic fibrosis, the somatic therapy targets the epithelial cells lining the lungs |
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If a parent with a disease has somatic therapy, their offspring could still inherit the disease. Explain why? |
Somatic therapy does not affect the individual’s sex cells (sperm or eggs) - so the DNA changes are not present in the gametes |
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What is germ line therapy? (Type of gene therapy) |
Involves altering the alleles in the gametes |
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A parent with a disease undergoes germ line therapy. What will be true of any offspring? |
• Every cell of an offspring produced from the cells of this parent will be affected by the gene therapy - mutated allele(s) not expressed • provided that the other parent doesn’t have the disease - the offspring will not suffer from the disease (won’t inherit) |
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Why is germ line therapy not widely used in humans? |
It’s illegal |
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What are the ethical issues surrounding gene therapy? |
• Technology could be used in other ways than medical treatment - e.g. treating the cosmetic effects of ageing • Potential to do more harm than good - e.g. overexpression of genes, gene produces too much of the missing protein (could harm cells) |
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What are the ethical issues surrounding gene therapy? |
• Technology could be used in other ways than medical treatment - e.g. treating the cosmetic effects of ageing • Potential to do more harm than good - e.g. overexpression of genes, gene produces too much of the missing protein (could harm cells) |
