Genetic Technology
SB2f Examine the use of DNA technology in forensics, medicine, and agriculture.
Genetic technology– Manipulating the genes of organisms
WHY might scientists want to change the DNA of organisms?
To improve organisms or to cure diseases.
Three examples of genetic engineering: Creating transgenic organisms Cloning DNA fingerprinting
1. Transgenic organism – contains genes of another organism
Ex- Tobacco with firefly gene
Bacteria are needed. Where is the DNA of a bacteria?
Two locations: a. Circular chromosome in cytoplasm b Two locations: a. Circular chromosome in cytoplasm b. Plasmid – small, circular piece of DNA
How to make transgenic bacteria: 1 How to make transgenic bacteria: 1. DNA of bacterial plasmid is cut with restriction enzymes 2. New gene is inserted 3. “Tape” the gene in place with ligase. 4. Plasmid replaced in bacteria 5. Bacteria make the protein coded by the new gene.
Bacteria can do this because they have the same genetic code as humans and all other living things. Bacteria used to produce human proteins insulin growth factor hormones
Ex - Mouse on right has a human gene that produces growth factor Ex - Mouse on right has a human gene that produces growth factor. Same technique used in chickens, pigs, and cows.
Traits put into transgenic plants: herbicide resistant gene insect resistant gene herbicide resistant gene drought resistant gene cold resistant gene disease resistant gene
Name 4 good reasons for creating transgenic organisms.
2. Cloning: making exact copies of organisms. Dolly was first
First cloned kitten.
Why Clone? A. Cloning stem cells for research Stem cells can develop into any type cell. They might be used to repair damaged or diseased organs and tissues.
B. "Pharming" for drug production Cows, sheep and goats are being genetically engineered to produce drugs or proteins that are useful in medicine.
C. Reviving Endangered or Extinct Species Clone endangered species
Name 3 good reasons for cloning.
3. DNA Fingerprints Use “genetic fingerprinting” to identify individuals. Each person’s DNA creates unique pattern. Steps: A. DNA is cut into small pieces with restriction enzymes. B. The pieces are separated and form bars. Then photographed.
C. Patterns of bars are compared to find a match. In this example, suspect #2 left some DNA at the crime scene.
Role of Biological Resistance Antibiotic resistance- the ability of a microorganism to resist the effects of an antibiotic. Occurs naturally through natural selection by random mutation. Or can be engineered. Resistance is passed on to offspring. Pesticide resistance- decreased susceptibility of a pest to a pesticide that was previously effective at controlling the pest population. Due to physiological and behavioral changes