What is Cloning?

An exact genetic copy of an organism

(identical twins are natural clones)

Two Ways to Do It

Artificial embryo twinningSomatic cell nuclear transfer

What????????

Artificial Embryo Twinning

Separate an early embryo into two cellsAllow each to divide and develop on its

ownPlace in a surrogate motherAllow to grow and develop

Somatic Cell Nuclear Transfer

Somatic cells are cells in the body except the sperm and egg. Every somatic cell has two sets of chromosomes in a mammal. Isolate a somatic cell Transfer the nucleus to an egg cell that has had

its original nucleus removed The egg cell will develop like a fertilized zygote

(method used to create Dolly the sheep)

Dolly Dolly, the first mammal to be cloned

from adult DNA, was put down by lethal injection Feb. 14, 2003.

Prior to her death, Dolly had been suffering from lung cancer and crippling arthritis.

Although most Finn Dorset sheep live to be 11 to 12 years of age, postmortem examination of Dolly seemed to indicate that, other than her cancer and arthritis, she appeared to be quite normal.

The unnamed sheep from which Dolly was cloned had died several years prior to her creation.

Dolly was a mother to six lambs, bred the old-fashioned way.

Cloned Foods

Currently there are only a small number of cloned farm animals in the United States. According to a recent Washington Post, there

are 150 cloned cows out of 9 million dairy cows in the United States, which each clone costing about $20,000 to produce.

The expense alone should keep the number down.

Draft Risk Assessment

Something we could do

Copies of the Draft Risk Assessment may be requested from the Communications Staff (HFV-12), Center for Veterinary Medicine, Food and Drug Administration, 7519 Standish Place, Rockville, MD 20855, and may be viewed on the Internet at http://www.fda.gov/cvm/cloning.htm

FDA is seeking comments from the public on the three documents for the next 90 days. To submit electronic comments on the three documents, visit http://www.accessdata.fda.gov/scripts/oc/dockets/comments/commentdocket.cfm?AGENCY=FDA. Written comments may be sent to: Division of Dockets Management (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD, 20852. Comments must be received by Apr. 2, 2007 and should include the docket number 2003N-0573.

Genetically Modified Foods and Organisms

Genes from different organisms that improve taste and nutritional value or provide resistance to particular types of disease can be used to genetically engineer food crops.

Uses recombinant DNA technology What????

1996 1st biotech crops on 7 million acres

2006 = 252 million acres This is 13%

more than in 2005

http://www.bio.org/ataglance/acreage.asp

GM Foods

In 2003, about 167 million acres (67.7 million hectares) grown by 7 million farmers in 18 countries were planted with transgenic crops, the principal ones being herbicide- and insecticide-resistant soybeans, corn, cotton, and canola.

Other crops grown commercially or field-tested are a sweet potato resistant to a virus that could decimate

most of the African harvest, rice with increased iron and vitamins that may alleviate

chronic malnutrition in Asian countries, and a variety of plants able to survive weather extremes.

US Department of Energy

U.S. Department of Energy Human Genome Program, http://www.ornl.gov/hgmis.

Cloning DNA in Plasmids

By fragmenting DNA of any origin (human, animal, or plant) and inserting it in the DNA of rapidly reproducing foreign cells, billions of copies of a single gene or DNA segment can be produced in a very short time. DNA to be cloned is inserted into a plasmid (a small,

self-replicating circular molecule of DNA) that is separate from chromosomal DNA.

When the recombinant plasmid is introduced into bacteria, the newly inserted segment will be replicated along with the rest of the plasmid.

http://www.biology.arizona.edu/

Cut DNA with restriction enzyme

Join vector and DNA fragment using DNA ligase

Recombinant molecule

Introduce recombinant into bacterium

image credit: U.S. Department of Energy Human Genome Program, http://www.ornl.gov/hgmis.

Inserting Bt toxin gene into corn

Isolate the genetic material in Bt

Insert gene into DNA carrier

Vector carrier into the plasmid

Plasmid inserts DNA into the corn cell genome

Grow your corn!

Art by Jiang Long and Jen Philpot

Bt Corn

A bacterium, Bacillus thuringiensis, and the gene of interest produces a protein that kills Lepidoptera larvae (European corn borer).

This protein is called the Bt delta endotoxin.

Growers use Bt corn as an alternative to spraying insecticides for control of European and southwestern corn borer.

The Bt gene, from Bacillus thuringiensis, produces a toxin that protects against caterpillars, reducing applications of insecticides and increasing yields.

The glyphosate resistance gene protects food plants against the broad-spectrum herbicide Roundup, which efficiently kills invasive weeds in the field.  

The major advantages of the "Roundup Ready®" system include better weed control, reduction of crop injury, higher yield, and lower environmental impact than traditional herbicide systems.

In 2004, approximately 85% of soy and 45% of corn grown in the U.S. were grown from Roundup Ready® seed.

Most Americans would probably be surprised to learn that more than 60% of fresh vegetables and processed foods sold in supermarkets today are genetically modified by gene transfer.

http://www.dnalc.org/home.html

Taste Testing SoonWednesday Sam Ball (Guest Speaker)

about what we are doing on campus for sustainability

Next exam questions soon too

http://vm.cfsan.fda.gov/~lrd/biotechm.html