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Biotechnology. Making the products you buy. . . better?. Historical Technologies: Applied Genetics. Manipulation of the hereditary characteristics of an organism to improve or create specific traits in offspring e.g., selective breeding, hybridization.
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Biotechnology Making the products you buy. . . better?
Historical Technologies: Applied Genetics • Manipulation of the hereditary characteristics of an organism to improve or create specific traits in offspring • e.g., selective breeding, hybridization
Historical Technologies: Applied Genetics • Selective breeding → Allowing only those individuals with the desired traits to reproduce
Historical Technologies: Applied Genetics • Hybridization → crossing different individuals to bring together the best traits of both organisms • Produces hybrid offspring that are often hardier than the parents
e.g., commercial chickens X White Rock Chicken: Grows quickly White Cornish Chicken: Grows large Commercial chicken: Grows to a large full size in only 6 weeks
Modern Technologies: Genetic Engineering • Altering an organism’s genetic code (DNA) to get it to express desired traits http://images.google.com/imgres?imgurl=http://www.peaceproject.com/graphics/dvds/larger/DVD51.jpg&imgrefurl=http://www.peaceproject.com/books/dvd51.htm&h=425&w=301&sz=34&hl=en&start=4&tbnid=z2kXaaU36oWWsM:&tbnh=126&tbnw=89&prev=/images%3Fq%3Dgenetically%2Bmodified%26gbv%3D2%26hl%3Den%26safe%3Dactive%26sa%3DX
e.g., Bt corn • Bacillus thuringiensis (Bt): a bacterium that produces a caterpillar toxin • The gene for this toxin has been inserted into this corn’s genome, which causes it to produce the toxin
e.g., spider silk • A spider’s silk-making gene has been inserted into a goat, which then produces silk in its milk http://www.chm.bris.ac.uk/motm/spider/goat.jpg http://www.kevhopgood.co.uk/New%20Stuff/Spider-Goat.jpg http://rockgardn.easystorecreator.com/images/images_919/JRFJ-Front-LG.gif
e.g., golden rice • Daffodil genes for making beta-carotene are inserted into the genome of rice http://www.jewishworldreview.com/toons/varvel/biotech.protest.gif http://www.bairesbiotec.org.ar/images/speake1.jpg
e.g., human insulin • Previously, humans with diabetes used insulin derived from the pancreas of cows and pigs (limited production) • Today, most human insulin comes from human insulin-making genes transferred into simple cells such as bacteria or baker’s yeast (unlimited supply) • Identical to insulin made by the human pancreas
Recombinant DNA in bacteria • Recombinant DNA → taking a piece of one DNA and combining it with another strand of DNA • Often, fast-growing single-celled organisms are used • e.g., bacteria • A piece of DNA that codes for a protein we want more of (e.g., human insulin) is spliced into the DNA of the fast-growing organism http://img.blogcu.com/uploads/kedicikkopekcik_insrton.jpg
Modern Technologies: Genetic Engineering • Gene therapy → adding a corrected copy of a gene to a person with a mutated gene to treat a disease • e.g., Cystic Fibrosis • Does NOT change the person’s genetic code! • Effect is temporary
Restriction Enzymes: Enzymes that cut DNA at certain sequences. http://www.accessexcellence.org/RC/VL/GG/images/restriction.gif