What is cloning?

• “assisted reproductive technology”• Ability to create genetically identical organisms by

transferring genetic information from one animal into an egg cell– Cloning does NOT change DNA

Why clone?

• Helps to maintain high quality livestock– Humans would eat the offspring of clones, not the

clone itself (ex. chickens from the Clone movie)• Quickly reproduces high quality livestock • Can be used to protect endangered species• Could help cure diseases and support organ

transplants (called Therapeutic Cloning)• Could allow infertile people to have children

How is an organism cloned?

• Artificial Embryo Twinning• Somatic Cell Nuclear Transfer

How is an organism cloned?

• Artificial Embryo Twinning1. Sperm cell fertilizes egg cell (cell is now called

embryo)2. Embryo naturally splits in two3. Scientist splits the two cells and puts them in

separate Petri dishes4. The cells divide and grow5. Cells go into surrogate mothers6. Identical twins are born

How is an organism cloned?

• Somatic Cell Nuclear Transfer1. Start with somatic cell (all chromosomes are

included)2. Empty nucleus from an egg cell3. Use electric shock to cause somatic cell and egg

cell to join (cell now called an embryo)4. Place embryo into surrogate mother5. Embryo grows and develops until clone is birthed

Successfully Cloned Animals

Risks of Cloning

• High failure rate – Success rate of 0.1 - 3%, • For every 1000 tries, 30 clones are made

• Clones are much bigger at birth and have abnormally large organs – Can lead to breathing problems, blood flow

problems, kidney or brain malformations, and impaired immune systems

Costs

• Cloning a cow costs between $10,000 and $20,000

Genetic Technology/Engineering• Genetic Technology provides

opportunities to change plants and animals genetically

• It can change the living world as we know it

• Includes:1.) Selective breeding2.) Biotechnology/genetic

engineering: Genetically Modified organisms

1.) Selective Breeding• Selective breeding is used to produce

organisms with desired traits• 2 ways to selectively breed:– Hybridization: Crossing two dissimilar

organisms to bring the best traits from both together• ex. Limequat and Tangelo

– Inbreeding: Crossing two very similar or closely related individuals in order to maintain a desired trait• ex. Dog breeding

Selective Breeding• Hybridization: ex. Limequat and Tangelo

• Inbreeding: ex. Dog breeding

2.) Biotechnology/genetic engineering

• Biotechnology/Genetic engineering involves manipulating DNA to transform organisms – makes it possible to cross genes that would not

normally happen in nature– involves cutting DNA from one organism and

inserting into the DNA of another (creates recombinant DNA)

– transgenic organisms – contain functional recombinant DNA from an organism of a different genus

Genetic Engineering: How do you insert DNA?

3 step process:1.) Isolate foreign DNA– Uses restrictive enzymes – bacterial proteins that can cut

DNA strands into specific nucleotide sequences2.) Attach DNA fragment to a carrier– uses vectors

• mechanical – micropipette, gene gun• biological – virus, plasmid (bacterial DNA)

3.) Transfer into host organism

Biotechnology/Genetic Engineering:

• Genetic Engineering results in:– Transformation: New DNA put into a new cell– Transgenic Organisms: Contains genes from other

species

Genetic Modification

• Combination of biotechology/genetic engineering and selective breeding

• Results in genetically modified organisms (GMOs)

• Almost everything has been genetically modified

• Usually used to make things bigger and better• Used a lot today with food

Possible Benefitsof GM Foods

Easing of world hunger Development of crops that

can be grown in marginal soil

Reduced strain on nonrenewable resources Development of drought

resistant crops Development of salt-

tolerant crops Development of crops that

make more efficient use of nitrogen and other nutrients

Possible Benefits of GM Foods

Reduced use of pesticides and herbicides►Development of pest

resistant crops ►Reduced herbicide

use is better for the environment and reduces costs for farmers

Possible Benefits of GM Foods

Improved crop quality Development of frost resistant

crops Development of disease

resistant crops Development of flood resistant

crops Improved nutritional quality

Development of foods designed to meet specific nutritional goals

Who makes sure GM foods are safe?

Government agencies regulate GM foods GM foods in the United

States are required to be labeled only if the nutritional value is changed or a new allergen is introduced.

Possible Risks of GM Foods

Insects might develop resistance to pesticide-producing GM crops

Herbicide-tolerant crops may cross-pollinate weeds, resulting in "superweeds"

Possible Risks for GM Foods

Certain gene products may be allergens, thus causing harm to human health

There may be unintended harm to wildlife and beneficial insects

Photo courtesy of T. W. Davies, Cal. Acad. of Sciences.

• fragments placed in “wells” formed in gel• electric field is applied forming +/- ends• DNA fragments separate based on size and

charge (smallest moves farthest away from wells)

Gel Electrophoresis:A method used to determine exactly what DNA fragments have been formed by restriction enzyme cutting

Other Genetic Technologies:

Human Genome Project

• Began in 1990. • The goal was to analyze the

entire human DNA sequence (6 billion base pairs)

• Originally scheduled to be completed in 2005

• In June 2003, the map was completed

• Cloning may be the next step

Human Genome Project