1. Genetic engineering alters genetic code of an orgaism. Gene giving desirable characteristics removed from one organism then inserted into anotehr organisms.
2. Able to transfer genes from one organism into another because genetic code is universal (same four bases used in DNA of all organisms).
3. Genetically modified organism is called transgenic organism.
Five Main Steps to Genetic Engineering
Whatever gene or organisms, these are the five main steps:
1. Identify gene wanted from an organism.
2. Remove gene that you're after in an organism.
3. Cut open DNA of organism you want to put gene in.
4. Insert gene into the DNA of second organism, where gene should now work.
5. Host is now transgenic organism, can clone it to make new species.
Cutting and inserting of DNA done using enzymes.
Bacteria and Human Insulin
Idea is to put human insulin gene into bacteria so bacteria can make human insulin. Modified bacteria reproduce and you get millions of insulin-producing bacteria.
1. Scientists identify gene controlling production of human insulin.
2. Remove it from DNA of human cell by cutting it out with restriction enzymes leaving DNA with 'sticky-ends'.
3. Loop of bacterial DNA called plasmid then prepared for insulin gene to be inserted. Restriction enzymes used to cut open plasmid, leaving it with 'sticky-ends' too.
4. Insulin gene inserted into plasmid, sticky ends allow ligase enzyme to join DNA strands together. Plasmid taken up by bacteria. Plasmid known as vector, something that carries a gene into another organism.
5. Bacteria now transgenic organism, checked to make sure they contain new gene by assaying techniques and cultured by cloninh. Millions of bacteria can be produced allowing large quantities of insulin to be harvested.