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Genetic engineering🧬
Genes from the chromosomes of humans and other organisms can be cut out using enzymes and transferred to cells of other organisms.
GM = Genetically modified
Examples of uses in food production:
- GM soya
- GM tomatoes
- Enzymes used to make vegetarian cheese
Examples of uses in medicine:
- Vaccine production
- Production of Factor VIII for haemophiliacs
Example in detail: Insulin production for diabetics.
What is insulin?
- Hormone made in the pancreas
- Controls blood sugar levels
- Allows glucose to be stored as glycogen
What is diabetes?
- Condition where people cannot produce their own insulin
- This means they cannot control their blood sugar levels
Genetic engineering uses
- Restriction enzymes – enzymes that ‘cut’ out sections of DNA
- Plasmids – circular pieces of DNA found in bacteria
- Bacteria – simple, unicellular organisms
- Ligase enzymes – enzyme that binds DNA together
The Process🔬
- Cut out the insulin gene from the DNA of a human cell using an enzyme.
- Remove a ring of DNA (a plasmid) from a bacterium and open it up using the same enzyme.
- Insert the insulin gene into the plasmid using another enzyme.
- Enable a bacterium to take up the altered plasmid.
- Put the bacterium in a fermenter, and it multiplies many times.
- Each new bacterium contains the plasmid with the insulin gene.
- The bacteria produce insulin which can be extracted.
Other uses of genetic engineering
In I/GCSE Biology, we need to know that genes can also be transferred to the cells of animals or plants at an early stage in their development so that they develop with desired characteristics:
- Gene therapy in could be used to insert healthy genes into foetuses that would otherwise develop a genetic disease.
- Genes can be inserted into clumps of plant cells, so that the adult plant can produce a chemical that kills pests.
Concerns about genetic engineering
- Their may be long-term, unpredicted effects of consuming GM plants.
- Genes for pesticide resistance may spread form GM plants to their wild relatives, creating pesticide resistant weeds.
- People may want to manipulate the genes of their future children.
- Vegetarians may consume genes from animals if plants are genetically modified.
That's the end of the topic!
Drafted by Joey (Biology)
Reference:
https://getrevising.co.uk/resources/biology_revision_notes4