genetic engineering

Genetic EngineeringChapter 13

Test on Friday 03/13/09Reviewing Content Due 03/12/09

1-10 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 organsReproductive cloning –new individuals

The End