Genetic Engineering

II. Genetic engineering: Changing an organism’s DNA to make it more beneficial to humans

Genetic Engineering, cont. A. Recombinant DNA: DNA made from two separate species 1. A gene from one organism is “recombined” with another organisms DNA. B. Transgenic Organism: any organism that contains recombinant DNA. a. These new gene combinations could never be possible in nature

Researchers isolate a gene from an organism that has the trait they want to give to a plant. and cells are grown 1.Transgenic Plants

Just for Fun?- a glowing tobacco plant

What’s Next on Your Plate? What genes do we want them to have? Insect, Herbicide, and Fungal resistance Drought resistance Product quality Longer Shelf Life (Flavr Savr Tomato)

Transgenic Organisms: Plants Golden Rice The rice on the right is called Golden Rice. Its genome contains the gene for producing vitamin A from daffodils. This rice is healthier for people who do not get enough vitamin A in their diets. Example: Rice plants and daffodils can not cross pollinate with each other in nature.

Transgenic Organisms: Animals Animals are now being produced with genes that increase milk production and muscle mass (meat). Problem: unhealthy; legs cannot support weight

3. Transgenic Organisms: Bacteria Used to produce important medicines: a. Insulin for diabetics b. Human growth hormone (HGH) to treat pituitary dwarfism c. Anticoagulants for (for treating heart attack patients) Bacteria cultures Insulin

Human Genome Project A genome is an organism’s complete set of DNA A genome is an organism’s complete set of DNA Project began in 1990; Completed in 2003 Project began in 1990; Completed in 2003 Coordinated by National Institutes of Health (NIH) & U.S. Department of Energy (DOE) Coordinated by National Institutes of Health (NIH) & U.S. Department of Energy (DOE)

What is the Human Genome Project (HGP)? Goals of HGP Goals of HGP 1. Reading and determining the sequence of the 3 billion base pairs in the human genome. 2. Locating and identifying all genes in the human genome which there is about 30, Storing information into databases that are accessible to the public 4. and addressing ethical, legal, & social issues involved in using this information 4. Analyzing and addressing ethical, legal, & social issues involved in using this information and addressing Analyzing and addressing

Benefits of the Human Genome Project 1. We have located many diseased genes and genetic tests have been created. 2. Researching bacteria genomes furthered research for fuel & environmental clean-up 3. Improved technology for DNA forensic science 4. Other sequences completed for E. coli, yeast, simple round worm, fruit fly, rat & chimpanzee (model organisms for studying how similar genes work in humans.) Maps of chromosomes # 13 & # 17; show the location of BRCA 2 & BRCA 1 – breast cancer genes.

DNA Fingerprinting/Electrophoresis DNA fingerprinting: tool used by forensics scientists to identify a person using DNA. How it Works: 1. A sample of the person’s DNA is taken from blood, semen, bone, or hair. 2. DNA fragments are cut – Restriction enzymes cut DNA at specific sequences. Useful to divide DNA into manageable fragments.

Electrophoresis 3. DNA fragments are separated based on size and charge. 4. Phosphate groups are negatively charged 5. DNA is placed into a gel & connected to an electric current 6. DNA moves through the gel toward + pole; shortest lengths move the fastest & longest lengths move the slowest. 7. A characteristic banding pattern is produced and a photograph is taken 8. The banding pattern is unique for each person – thus called a DNA fingerprint

15 Electrophoresis

16 Electrophoresis

DNA Fingerprints Was any of the victims blood on the defendants clothing? Used as evidence in court cases Which dog was probably the culprit (dog that bit the person)?

How Cloning Occurs in Nature 1. Clone: an organism that is genetically identical to another organism a. All of the genes are the same (identical) 2. Examples of cloning that occurs in nature a. Reproduction in bacteria & sponges (asexual) b. Identical are natural clones b. Identical twins are natural clones

Bacteria and Plant Cloning is Easy 1. Cloning of transgenic bacteria creates many “living factories” used to make & other drugs 1. Cloning of transgenic bacteria creates many “living factories” used to make insulin & other drugs 2. Cloning of transgenic plants to insure genetics are intact for the next generation. Bacteria that contain genes for digesting oil can be used to clean up oil spills.

Animal Cloning is difficult and controversial Animal Cloning is difficult and controversial Dolly: First cloned animal Also called Reproductive Cloning

What are Stem Cells & Why Do Scientists Want Them? 1. Stem cells: (link) undefined cells that reproduce continuously & can develop into any type of cells or tissues Stem cells Stem cells 2. The hope is to be able to produce tissue & organs for transplants Stem cell technology can help those who wait for organ transplants.

Where do we get Stem Cells? a) Embryonic Stem cells are most easily obtained from embryos and umbilical cords. (work best) They are pluripotent. b) Adult Stem cells are found in bone marrow and skin.