BIOTECHNOLOGY BIOTECHNOLOGY TERMS Gel electrophoresis DNA fingerprint Transgenic
BIOTECHNOLOGY
BIOTECHNOLOGY TERMS Gel electrophoresis DNA fingerprint Transgenic Gene therapy Restriction enzymes Bacterial transformation Bioethics Cloning Stem cells Human Genome Project
DNA Fingerprinting (Profiling)
DNA Fingerprint l l DNA is extracted from cells Cut with restriction enzymes Fragments separated by gel electrophoresis Bands compared
Restriction Enzymes l l l Molecular scissors Cut DNA at a specific base sequence (recognition site) Can make blunt or sticky ends
Gel Electrophoresis DNA fragments separated by size l Electric current pulls DNA fragments through a gel Large fragments move slower; small fragments move faster l
Steps to DNA Fingerprinting (Profiling) l DNA is extracted from sample (skin, blood, etc. ) l DNA is “cut” with restriction enzymes to make different length pieces (restriction fragment length polymorphisms – rflps)
l fragments are then separated using gel electrophoresis l Electrophoresis Simulation Website http: //gslc. genetics. utah. edu/units/bio tech/gel/
l The gel is stained or Xrays taken, producing an obvious band of fragments resembling bar codes on products
DNA fingerprints can be used to. . . l diagnose genetic disorders and identify carriers
l analyze evidence at crime scenes (some placed in CODIS-Combined DNA Index System) l evidence of paternity l personal identity
Measure the Agar Powder
Dissolve the Powder and Heat
Casting the Tray
Loading the Wells
X-raying the Gel
Finished X-Ray of Gel
Complete the Gel Electrophoresis Virtual Lab! l http: //www. classzone. com/cz/bo oks/bio_07/resources/htmls/virtu al_labs/virtual. Labs. html
Bacterial Transformation l l l Foreign genes spliced into a bacterial chromosome (plasmid) Gene is “turned on” Foreign protein manufactured
Bacterial Transformation Bacteria will take in foreign DNA and manufacture proteins coded for in that DNA Discovery led to recombinant DNA Frederick Griffith
Recombinant DNA (r. DNA) l DNA from two organisms are combined l gene from one organism is spliced into another one
Process (1) Foreign gene is inserted into a bacterial plasmid (2) Bacteria take in the plasmid (through transformation) (3) Bacteria that are transformed are cultured (4) Bacteria produce the protein
Uses of Recombinant DNA l manufacture of insulin l manufacture of Factor VIII l manufacture of HGH (human growth hormone)
l TPA for dissolving blood clots (for patients that have had heart attacks) l vaccines such as for hepatitis B and Gardasil (the genes for virus proteins are inserted into yeast)
l medication that stimulates growth of bone marrow after a bone marrow transplant l anti-cancer medications
l GM (genetically modified) food crops In 2006, a total of 252 million acres of transgenic crops were planted in 22 countries by 10. 3 million farmers!
l most GM food crops are insect-resistant, droughtresistant, etc. l some GM foods are engineered to have increased levels of vitamins, such as golden rice
Are you eating GM foods? More than 60% of food products on grocery shelves contain some crop that has been genetically modified! l For example, 81% of the soybean products are GM l 60% of canola products are from GM canola plants l
Are you wearing GM plant products? l 71% of the cotton used in textiles is GM l (cottonseed oil can also be found in salad dressing, peanut butter, crackers, cookies, and other foods)
l genetically engineered bacteria to clean oil spills l larger amounts of ethanol for fuel (biofuel)
Transgenic l Organisms that have foreign genes inserted into their chromosomes
l transgenic animals in the future could be used for organ transplantation
Complete the Bacterial Transformation Virtual Lab!! l http: //www. classzone. com/cz /books/bio_07/resources/html s/virtual_labs/virtual. Labs. htm l
CLONING l Organisms with identical DNA are clones l Identical twins are clones l Plants produced by “rooting” are clones l Clones can be made by humans
l Some animals are cloned when they are damaged and divided, such as earthworms or starfish l We have cloned some animals by artificial means
Who Was Dolly?
In 1997, British scientists successfully cloned a sheep by transferring the nucleus from the cell of an adult sheep into the cytoplasm of an eunucleated fertilized egg. The egg was then transplanted into the uterus of a surrogate mother where it developed like a normal zygote into a lamb, which grew into a normal adult sheep called 'Dolly'
Nuclear Transfer
Benefits of Cloning l Survival of endangered species For example, a gaur is an endangered animal from Asia and has been successfully cloned
Maintenance of high quality livestock for food The U. S. Food and Drug Administration, in 2008, concluded that “edible products from normal, healthy clones or their progeny do not appear to pose increased food consumption risks relative to comparable products from conventional animals. ” l
l Economical importance – cloning favorite pets is expensive Cc (Carbon Copy)
l Genetics Savings and Clone was a company that cloned pets for $50, 000 l Without many customers, the company closed
Statement issued 4/2/09 by the Bio. Technology Industry Organization “The biotechnology industry has developed and commercialized more than 300 drugs and diagnostics that are helping more than 325 million people worldwide and another 400 or so products are in the pipeline. ”
The Human Genome Project goals were to l identify all the approximately 20, 000 -25, 000 genes in human DNA l determine the sequences of the 3 billion chemical base pairs that make up human DNA
Human Genome Project l Joint project by US and other countries to sequence all of the human DNA
l store this information in databases l improve tools for data analysis l we must address the ethical, legal, and social issues that may arise from the project
Francis Collins from the publicly-funded Human Genome Project and J. Craig Venter, head of the private company Celera Genomics, jointly announce a working draft of the human genome
Gene Therapy
Gene Therapy l Inserting normal genes into a person to correct a gene mutation l The “new” gene would be transcribed, then translated to produce normal protein
l Potential cures for genetic disorders such as hemophilia, sickle cell, and cystic fibrosis
l Or for cystic fibrosis
In 1990, Ashanti de Silva was the first person to be cured with gene therapy; cured of SCID
David Vetter from Texas had SCID and had to live in a sterile environment for most of his life during the 1970/80 s. He was known to the media as 'the boy in the plastic bubble' and wore a special 'spacesuit' to protect him from infections.
STEM CELLS Undifferentiated cells that have the genes to become any type of cell of that organism l Primarily found in embryos, but can also be found in adults, such as stem cells in the bone marrow that divide to make all blood cells l
l If cells can be induced to differentiate into a specific type of cell, they can be used to repair damage, such as people with permanent spinal cord injuries or potentially treat Parkinson’s
Bioethics l l l What is right and l Who has a right to wrong with get results from manipulating DNA? DNA testing? What is legal and An employer? An illegal? insurance Who gets to decide? company?
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