Gene Technology

• GMOs


  GMOs r also used to store a living record of the DNA of another organism in DNA libraries

  DNA sequencing projects enable scientists to build a collection of sequenced DNA fragments from that is then stored + propagated in MOs thru the process of genetic engineering

  these libraries serve as a source of DNA fragments for further genetic engineering applications/for further study of their function
• Genetically Engineered Pathogens


  not widely used in the applications of medical treatments + industrial processes for the obv health + safety of the researchers + wider public

  usually for the purposes of medical + epidemiological research + is strictly regulated
• Threat of Genetically Engineered Pathogens

  a concern that genetically engineered pathogens could be used for the purposes of biological warfare

  attempts to modify the genomes of pathogens to be more virulent/to be resistant to all known treatments, raises serious ethical concerns + is a largely prohibited area of research except in specialised military research facilities
• Insect Resistance in GM Soya Beans

  in one such modification, scientists have inserted a gene into soya beans so that they produce the Bt protein

  = toxic to many of the pest insects that attack the plant + is widely used as a pesticide by organic farmers

  one increasingly used strain of soya beans has been engineered to be resistant to be resistant to a common weed killer + to contain Bt protein

  = farmers can spray to get rid of weeds, making all the resources of light, water + minerals available to the beans + they dont need to use pesticides = higher yield
• Pest Resistance of GM Crops - Advantages

  pest-resistant GM crops reduce the amount of pesticide spraying , protecting the enviro + helping poor farmers

  increases yield
• Pest Resistance of GM Crops - Cons

  non-pest insects + insect-eating predators might be harmed by the toxins in the GM crops

  insect pests may become resistant to pesticides in GM crops
• Disease Resistance of GM Crops - Pros

  crop varieties resistant to common plant diseases can be produced, increasing yield
• Pharming - Creating Animal Models

  the addition/removal of genes so that animals develop certain diseases, acting as models for the development of new therapies

  e.g. knockout mice have genes deleted so they r more likely to develop cancer
• Pharming - Creating Human Proteins

  the intro of a human gene coding for a medically required protein

  animals r sometimes used cos bacteria cannot produce all of the complex proteins made by euks

  the human gene can be intro into the genetic material of a fertilised cow or sheep along w a promoter sequence so the gene is expressed only in the mammary glands

  the fertilised transgenic female embryo is then returned to the mother

  a transgenic animal is born + when it matures + gives birth, it produces milk

  = contains the desired human protein + can be harvested
• Somatic Cell Gene Therapy

  involves replacing the mutant allele w a healthy allele in the affected somatic cells

  successful treatment have been reported for diseases inc immune diseases, leukaemia + haemophilia
• Cons of Somatic Cell Gene Therapy

  somatic cell gene therapy is only a temporary solution for the treated individual

  the healthy allele will be passed on every time a cell divides by mitosis but somatic cells have a limited life + r replaced from stem cells, which will have the faulty allele

  in addition, a treated individual will still pass the faulty allele to any children they have
• Germ Line Cell Gene Therapy

  insert a healthy allele into the germ cells - usually the eggs or into an embryo immediately after fertilisation (part of IVF)

  the individual would be born healthy w the norm allele in place + would pass it on to their offspring

  such therapy has been successful w animal embryos but is illegal for humans in most countries cos of ethical + medical concerns
• Concerns about GM Crops - Patenting

  one of the major concerns about GM crops is that ppl in less economically developed countries will be prevented from using them by patents + issues of technology transfer
• Patenting GM Crops


  when someone discovers a new technique or invents something, they can apply for a legal patent, which means that no one else can use it w out payment

  the ppl who most need the benefits of drought/flood-resistant crops, high yields + added nutritional value may therefore be unable to afford the GM seeds