DNA Technology and Genomics

Genetic Engineering/ DNA Technology 3 types of Cloning Technologies: 1.Recombinant DNA Technology/ DNA Cloning 2. Reproductive Cloning 3. Therapeutic Cloning

Cloning the bovine growth hormone (BGH) gene

Recombinant DNA Technology/ DNA Cloning

Cloning a Gene Cloning means making many copies of a gene

Recombinant DNA Technology/ DNA Cloning 1. Remove the Gene of Interest 2. Cut the Plasmid DNA 3. Insert the Gene into the Bacterial Plasmid 4. Insert the Recombined Plasmid into the Bacterial Cell 5. Let the Bacteria Reproduce

1. Remove the gene of interest (ex: BGH gene) using restriction enzymes Restriction enzymes cut DNA at specific sequences called palindromes...

Restriction Enzymes Leave “Sticky Ends”

Restriction Enzymes The unpaired bases on the sticky ends form bonds with any complementary bases with which they come into contact

2. Cut the Plasmid DNA with the Same Restriction Enzyme

3. Insert the Gene of Interest into the Bacterial Plasmid (The bacterial plasmid is also cut with the restriction enzyme, leaving sticky ends)

4. Insert the Recombined Plasmid into a Bacterial Cell

5. Let the Bacteria Reproduce

Other Proteins Made by DNA Cloning: Insulin for diabetics Clotting factors for hemophiliacs

Basic Versus Applied Research Basic research no profit motive or direct commercial application – generally government funded Applied research immediate and profitable application – generally privately funded

Reproductive Cloning/Cloning Entire Organisms

Reproductive Cloning Technology used to generate an animal that has the same nuclear DNA as another curretly or previously existing animal

Steps in Nuclear Transfer

Steps in Somatic Cell Nuclear Transfer

Results of Nuclear Transfer Experiments There were 277 failures before this nuclear transfer technique succeeded;

Reproductive Cloning Dolly was successfully born in 1997

Reproductive Cloning Dolly was put to sleep at the age of 6 in 2003 She was suffering from arthritis and a progressive lung disease These are usually only seen in old sheep

Other Organisms Reproductively Cloned Mouse Cow Goat Mule Horse Rabbit Cat Pig Dog Rat Deer

Why Do Reproductive Cloning?

Have We Reproductively Cloned Humans?

Opposition and Support of Human Cloning

What do YOU think?

Therapeutic Cloning/ Embryo Cloning Instead of cloning entire organisms, there is therapeutic cloning Stem cells are induced to turn into specific tissue cells

Therapeutic Cloning

The Human Genome Project Sequenced the entire human genome

Goals of The Human Genome Project

Organisms With Genome Sequenced Rhesus Macaque Fruit Fly Zebra fish Potato

Many organisms have genome projects that have either been completed or will be completed shortly, including : Humans Neanderthal Haemophilus influenzae, a bacterium Common House Mouse Brown Rat Common Chimpanzee Rhesus Monkey Domestic Chicken Domestic Cat Domestic Dog Common fruit fly Baker's yeast

Many organisms have genome projects that have either been completed or will be completed shortly, including Red bread mold, Thale Cress Rice Common Wheat Corn Poplar Tree E. coli bacteria SARS virus Nematode worm Zebra fish Tomato Potato Western Honey Bee Grapevine Spanish flu virus

The Human Genome Project These were used as model organisms in genetic studies These model organisms contain genes that are the same as human genes

Gene Testing

DNA Chips

Pros and Cons of Gene Testing

Gene Therapy Once the genetics are worked out, gene therapy can be researched Replacing defective genes with functional ones –Germ line gene therapy in embryos –Somatic cell gene therapy in individual somatic cells in affected tissues

Gene Therapy Germ Line Gene Therapy Somatic Cell Gene Therapy

Gene Therapy Non disease causing virus is genetically engineered with the functioning gene that is needed in SCID patients The virus infects the immune cells and the immune cells get the functioning gene

Gene Therapy

Treatment for SCID (severe combined immunodeficiency) Gene therapy in cells of the immune system

Somatic Gene Therapy is not widely used Is only for single gene disorders with cells that can be removed, engineered and then replaced in the body

Somatic Gene Therapy The condition may still be passed to offspring, because somatic cell gene therapy does not treat all the cells in the body

Setbacks to Gene Therapy

1.Treat Cancer 2. Gene Therapy to treat inherited form of blindness is successful!Gene Therapy to treat inherited form of blindness is successful Recent Successes in Gene Therapy

Genetically Modified Crop Plants

Genetically Modified Food

Inserting the Gene

Pros to Creating Genetically Modified Food

Genetic Engineers Can Modify Food Transgenic organisms are produced when a gene from one organism is incorporated into the genome of another The more popular term for transgenic organisms is GMO, for genetically modified organism GM foods means genetically modified

Cons to Creating Genetically Modified Food

Genetically Modified Foods in the U.S. Diet Over half of all food in U.S. market contain at least some GM foods –Most soybeans grown are modified for herbicide resistance –GM corn – an ingredient in most processed foods – is common as well –GM canola and cottonseed oils are used in a huge range of food products

FDA Regulations Manufactures must get FDA approval for an food not generally recognized as safe (GRAS), including new genetically engineered food substances The FDA declared milk from rBGH cows safe for consumption in 1993

How Are GM Foods Evaluated for Safety? The EPA must approve all GM crops GM foods can cause allergic reactions (8% of us are allergic to foods) Newly inserted genes may also encode proteins that prove to be toxins