Genetic Engineering Unit Chapter 15

Slide # 2 Genetic engineering: changing an organism’s DNA to make it more beneficial to humans All of the different types of chili peppers are are result of selective breeding – a form of genetic engineering!

Slide # 3 A. Selective Breeding Selecting individuals with the desired traits to produce new offspring Used in agriculture to produce superior plant species Used to produce breeds of domestic animals – dogs, horses, cats, sheep, cattle 2. Also called artificial selection All of the different plants produced from wild mustard by selective breeding!

B. Limits of Selective Breeding Slide # 4 B. Limits of Selective Breeding Impossible to mix traits from two different species All of the organism’s genes are passed on – even undesirable traits Might want plants that are drought resistant; however, end up with plants that don’t produce many seeds! When breeding for drought resistance, instead of getting ears of corn like on the left, you might end up with ears of corn like on the right!

C. Types of Selective Breeding Slide # 5 C. Types of Selective Breeding Inbreeding: organisms are crossed with individuals that have similar traits. Preserves well adapted genotypes In plants, insures pollination w/out insects Decreases genetic variation (differences) Self-pollination is a form of inbreeding.

2.Hybridization: crossing 2 dissimilar, but related organisms Slide # 6 2.Hybridization: crossing 2 dissimilar, but related organisms - Usually stronger/hardier than parents – known as hybrid vigor - May promote the loss of native species 1. African catfish (left) grows faster than Thai catfish. 2. Thai catfish (middle) has better tasting flesh than African catfish. 3. Hybrid (right) grows fast & has good tasting flesh.

Check out animation on wiki

Slide # 8 D. Recombinant DNA Recombinant DNA: made from pieces of DNA from different organisms; the pieces stick together DNA from different organisms are “recombined” How recombinant DNA is made:

E. Transgenic Organisms: Plants Slide # 9 E. Transgenic Organisms: Plants Definition: any organism that has genes from a different organism inserted into its DNA. Genomes can be produced that could never be produced by nature EX: Rice plants and daffodils usually do not cross pollinate each other in nature 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.

F. Transgenic Organisms: Animals Slide # 10 F. Transgenic Organisms: Animals Genetically engineered mice used in cancer research: Contain gene from glowing jellyfish Glow when a cancer is growing in them Mice are given chemotherapy drugs; if the tumor shrinks, they glow less & less Mice don’t die from cancer or drugs Mice expressing “glow” gene from jellyfish. Glowing jellyfish

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

CLONING NOW Bacteria and Plant Cloning is Easy 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. 3. Save a species? Bacteria that contain genes for digesting oil can be used to clean up oil spills. (2010 BP oil spill)

G. How Animals are Cloned (SOMATIC CELL NUCLEAR TRANSFER) Dolly: First cloned animal Reproductive Cloning

First Cloned Cat (2001)

DNA Fingerprinting: Used in DNA Forensics 1. DNA fingerprinting: tool used by forensics scientists to identify a person using DNA. 2. How it Works: A sample of the person’s DNA is taken from blood, semen, bone, or hair. DNA fragments are placed into a gel & connected to an electric current DNA moves through the gel; shortest lengths move the fastest & longest lengths move the slowest. A characteristic banding pattern is produced and a photograph is taken The banding pattern is unique for each person – thus called a DNA fingerprint

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

What are Stem Cells & Why Do Scientists Want Them? Stem cells: undefined cells that reproduce continuously & can develop into any type of cells or tissues 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? Embryonic Stem cells are most easily obtained from embryos and umbilical cords. (work best) 2. Adult Stem cells are found in bone marrow.

What is the Human Genome Project (HGP)? 1. Began in 1999; Completed in 2003 2. Coordinated by National Institutes of Health (NIH) & U.S. Department of Energy (DOE) 3. Goals of HGP Identify all genes in the human genome Determine the sequence of all 3 billion DNA base pairs (Gene mapping) Store the information into databases Address ethical, legal, & social issues that arise from human genome research

Benefits of the Human Genome Project Find where genes are located on the chromosomes and what each is for. (Many diseased genes have been found.) 2. Furthered research for fuel & environmental clean-up (bacteria genomes) 3. Improved technology for DNA forensic science Maps of chromosomes # 13 & # 17; show the location of BRCA 2 & BRCA 1 – breast cancer genes.