Genetic Engineering

• Genetic engineering involves changing the DNA in living organisms to create something new
• Organisms with altered DNA are called Genetically Modified Organisms (GMO)
• Examples of GMOs include bacteria that produce human insulin
• Genetic engineering techniques include artificial selection, cloning, gene splicing, and gel electrophoresis
• Artificial selection involves breeders choosing which organisms to mate to produce offspring with desired traits
• Three types of artificial selection are selective breeding, hybridization, and inbreeding
• Selective breeding occurs when animals with desired characteristics are mated to produce offspring with those traits
• Examples of selective breeding include Angus cows bred for increased muscle mass and egg-laying hens bred for higher egg production
• Hybridization involves crossing individuals with different characteristics to produce the best traits in the offspring
• Inbreeding is breeding organisms that are genetically similar to maintain desired traits
• Cloning creates an exact genetic copy of an organism
• Dolly the sheep was the first mammal cloned
• Cloning involves removing a cell from an organism, growing it, and placing it into a surrogate mother
• Cloning can be used in plants and animals
• Gene splicing is the process of cutting DNA from one organism and inserting it into another
• A specific trait can be transferred from one organism to another through gene splicing
• For example, the human insulin gene can be inserted into a bacterial cell
• Gene splicing involves transferring a trait from one organism to another
• Example: Human insulin gene can be removed from a human cell and put into a bacterial cell
• Bacteria will now produce human insulin
• DNA is too small to be seen without a microscope
• Recombinant DNA is created by combining the insulin gene from a human with DNA from a bacteria
• Benefits of gene splicing:
• Insulin is cheaper
• No side effects because it is human insulin
• Previously used pig insulin had side effects and was more expensive
• How gene splicing is done:
• A restriction enzyme cuts the insulin gene out of human DNA
• A plasmid from a bacteria is cut with a restriction enzyme
• The human gene is inserted into the bacterial plasmid
• The plasmid is placed back into the bacteria, which now has the DNA to produce insulin
• This process results in the production of human insulin by bacteria
• Transformation:
• Refers to when a gene from one organism is transferred to a different organism
• Organisms that have had DNA transferred to them are called transgenic organisms
• Genetic engineering techniques:
• Transgenic animals: genes inserted to produce what humans need
• Transgenic plants: genes inserted to meet human needs, e.g., corn producing a natural pesticide
• Recombinant DNA technology has led to the field of biotechnology
• Gene therapy: