Genetic Engineering

Chapter 13Chapter 13

Selective breeding

Allowing animals with certain traits to Allowing animals with certain traits to breed to produce a desired offspring.breed to produce a desired offspring.

Examples:Examples:

Luther Burbank (1849-1926)

American botanist American botanist who developed the who developed the disease resistant disease resistant Burbank potatoBurbank potato

Used process of Used process of hybridizationhybridization : : crossing dissimilar crossing dissimilar organisms to get best organisms to get best of both qualities.of both qualities.

Inbreeding

The controlled breeding of closely related The controlled breeding of closely related organisms.organisms.

Positive effects: controlled traits and Positive effects: controlled traits and characteristics. Pure bred dogscharacteristics. Pure bred dogs

Negative effects: excessive inbreeding can Negative effects: excessive inbreeding can produce unwanted effects because of lack produce unwanted effects because of lack of variation. Blindness in German of variation. Blindness in German shepherdsshepherds

Increasing variation

Use radiation or Use radiation or chemicalschemicals

Can produce new strains Can produce new strains of bacteria and new of bacteria and new plants. plants.

Polyploidy

Having a multiple of Having a multiple of the normal the normal chromosome number.chromosome number.

Example: regular Example: regular chromosome number chromosome number is 9. Polyploidy is 9. Polyploidy condition could be 18, condition could be 18, 27, 36, etc.27, 36, etc.

DNA manipulation

1.1. Cutting DNACutting DNA

2.2. Copying DNACopying DNA

3.3. Changing DNAChanging DNA

DNA Extraction

Where is the DNA Where is the DNA located in a cell?located in a cell?

-the nucleus-the nucleus First must break apart First must break apart

the cell membrane and the cell membrane and nucleus to get at the nucleus to get at the DNADNA

Cutting DNA

Usually use a Usually use a restriction restriction enzyme : enzyme : a a chemical used to chemical used to cut out a specific cut out a specific segment of DNA.segment of DNA.

Gel Electrophoresis

Placing a mixture of Placing a mixture of DNA into a gel and DNA into a gel and applying an electric applying an electric current. DNA is then current. DNA is then separated according to separated according to size.size.

Reading the DNA

Using a computer, fluorescent dyes, and Using a computer, fluorescent dyes, and samples of adenine, guanine, cytosine, and samples of adenine, guanine, cytosine, and thymine.thymine.

Cutting and Pasting

Use DNA synthesizers to make Use DNA synthesizers to make recombinant DNA (DNA from two recombinant DNA (DNA from two different organisms spliced together)different organisms spliced together)

Making copies

PCR polymerase.PCR polymerase. Used to make Used to make

multiple copies multiple copies of a segment of of a segment of DNA or gene.DNA or gene.

Developed by Developed by Kary MullisKary Mullis

Transformation

When a cell (usually a bacterium) When a cell (usually a bacterium) takes in DNA from outside the cell.takes in DNA from outside the cell.

Example: Griffith’s ratsExample: Griffith’s rats

Plasmids

A small circular A small circular molecule of DNAmolecule of DNA

1.1. It often has a DNA It often has a DNA sequence that serves sequence that serves as an origin of as an origin of replication.replication.

2.2. Contain genetic Contain genetic markers.markers.

Transgenic organisms

When an organism When an organism contains genes from contains genes from other organisms.other organisms.

Example:Example: A tobacco plant that A tobacco plant that

containd DNA from containd DNA from a firefly. a firefly.

Biotechnology

A “new” field of biology that utilizes A “new” field of biology that utilizes genetic engineering to produce new genetic engineering to produce new substances in the fields of health and substances in the fields of health and industry.industry.

Transgenic animals

Livestock can grow Livestock can grow faster, better quality of faster, better quality of meat, resistant to meat, resistant to disease.disease.

Cows that produce Cows that produce human proteins in human proteins in their milk.their milk.

Transgenic plants

Usually cash crops Usually cash crops such as cotton, corn, such as cotton, corn, wheat, soybeans, etc.wheat, soybeans, etc.

Often incorporates Often incorporates bacterial DNA to bacterial DNA to make the crop resistant make the crop resistant to disease, pests, or to disease, pests, or chemicals.chemicals.

Ex: Ex: BtBt corn corn

Cloning

Clone: a member of a Clone: a member of a population of population of genetically identical genetically identical cells produced from a cells produced from a single cell.single cell.

1997: first mammal 1997: first mammal cloned. Dolly, the cloned. Dolly, the sheep.sheep.

How do you make a clone?

Is cloning a good thing or a bad thing? Cloning articlesCloning articles

Assignment:

Page 337-338Page 337-338 1-10, 13, 16, 17, 22, 23, 321-10, 13, 16, 17, 22, 23, 32