Genetic Engineering Chapter 13 Test on Friday 03/13/09 Reviewing Content Due 03/12/ and #28

What is Genetic Engineering? Engineering – science of matter made useful to man Genetics - how traits are passed on through generations. Genetic Engineering - manipulation of an organism's genetic material to modify the proteins it produces.

Types of genetic engineering: Indirect genetic manipulation Direct genetic manipulation

Indirect Genetic Manipulation Selective Breeding - desired characteristics (phenotypes) are allowed to produce Hybridization – crossing dissimilar characteristics (phenotypes) to bring together the best Inbreeding – continued breeding of individuals with similar characteristics Induced Mutations – inducing mutations -  new genetic combinations -  new phenotypes (variation)

Direct Genetic Manipulation: Scientists use their knowledge of DNA structure & chemical properties to change (manipulate) DNA. DNA  RNA  Proteins -  Phenotypes

How do you Manipulate DNA: DNA Extraction – cells are opened and DNA removed We will do this in class

Cutting DNA DNA is cut into small pieces (WHY?) Restriction enzymes - cuts DNA at specific nucleotide sequences Hundreds of restriction enzymes are known

Seperating DNA How can DNA fragments be analyzed once extracted and cut,

gel electrophoresis

Use of DNA Reading the Sequence – complementary base pairing of fragments of DNA – The nucleotides (A,T,C,G) is color coded – The fragments are separated by gel electrophoresis – The order of the colors -  order of nucleotides

Cut & Pasting DNA sequences can be joined together using synthesizers – Recombinant DNA – combining DNA from different sources, usually in the form a plasmid Natural DNA  Natural DNA Natural DNA  Synthetic DNA (created)

Making Copies Polymerase Chain Reaction – makes many copies of DNA fragments for study – Copying of DNA

Review: What was Griffith’s Experiment? Griffith’s experiments he heated the smooth (lethal) pneumonia strain mixed it with the rough (non-lethal) strain, there must have been DNA fragments from the lethal that were taken in the non-lethal -  lethal

Cell Transformation When cells either bacterial, plant, or animal takes in external DNA, that becomes incorporated into the cells DNA. This external DNA can be in the form of a plasmid.

Types of Transformation: Bacterial new gene inserted into the bacterial plasmid Recombinant plasmid is reinserted into the bacteria

Types of Transformation: Plant New gene is inserted into the bacterial plasmid Bacteria then infects the plant cell. Successful when recombinant DNA is integrated into the cells chromosomes (DNA)

Types of Transformations-Animal New gene inserted in bacterial plasmid The plasmid inserted directly into nucleus of animal cell. New DNA is incorporated into the animal chromosomes – transcription  translation  recombinant protein production

Diagram – Transformation Bacterial

Transgenic Organisms organisms with foreign DNA – Bacteria with foreign genes used to create medicine Insulin, growth hormone, clotting factor

Transgenic Organisms – Animals – extra genes used to create livestock that can produce more food or study human disease – Plants – extra genes create more food, resistance to disease, insects, or chemicals for weed control

Applications of Genetic Engineering: Biotechnology industry both commercial & therapeutic is spurred by genetic engineering techniques.

Cloning process of creating exact copies of organisms – Application unclear

Therapeutic applications New organs Reproductive cloning – new individuals