Applications of Genetic Engineering 13-4 Ms. Haut Transgenic Organisms Copyright Pearson Prentice Hall http://www.bio.miami.edu/~cmallery/150/handouts/D.zebra.htm http:// http://www.bio.miami.edu/~cmallery/150/handouts/c17 x5transgenic-tobacco.jpg • An organism described as transgenic, contains genes from other species. Transgenic Organisms • Genetic engineering has spurred the growth of biotechnology. – Transgenic animals and plants – The Human Genome Project – The production of vaccines, cancer drugs, and pesticides – Engineered bacteria that can clean up toxic wastes – Cloning • Organ replacement Copyright Pearson Prentice Hall • Transgenic bacteria produce important substances useful for health and industry. Transgenic bacteria have been used to produce: – insulin – growth hormone – clotting factor Copyright Pearson Prentice Hall BIOLOGY: CONCEPTS AND CONNECTIONS 4th Edition, by Campbell, Reece, Mitchell, and Taylor, ©2003. Transgenic Organisms • Transgenic animals have been used to study genes and to improve the food supply. • Mice have been produced with human genes that make their immune systems act similarly to those of humans. This allows scientists to study the effects of diseases on the human immune system. http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=cmed&part=A9538 Transgenic Organisms Copyright Pearson Prentice Hall Transgenic Animals • Nils Lonberg, director at Medarex, bred two genetically modified mice, creating a mouse with a humanized immune system. • In response to diseasecausing agents, these mice make human antibodies in their cells, some of which might be developed into drugs. http://images.businessweek.com/ss/06/01/critters/source/4.htm Transgenic Organisms • Researchers are trying to produce transgenic chickens that will be resistant to the bacterial infections that can cause food poisoning. Copyright Pearson Prentice Hall http://www.cals.ncsu.edu/agcomm/magazine/spring03/images/transgenic1.jpg Transgenic Organisms • Transgenic plants are now an important part of our food supply. • Many of these plants contain a gene that produces a natural insecticide, so plants don’t have to be sprayed with pesticides. Copyright Pearson Prentice Hall • Bt Corn – Engineering resistant corn. Following the insertion of a gene from the bacteria Bacillus thuringiensis, corn becomes resistant to corn borer infection. This allows farmers to use fewer insecticides http://www.bio.davidson.edu/people/kabernd/semin ar/2004/GMevents/LH/cornear.jpg Transgenic Plants http://www.scq.ubc.ca/bt-corn-is-it-worth-the-risk/ • “Golden rice” has been genetically modified to contain beta-carotene – This rice could help prevent vitamin A deficiency Figure 12.18B Cloning Dolly and Bonnie • A clone is a member of a population of genetically identical cells produced from a single cell. • In 1997, Ian Wilmut cloned a sheep called Dolly. Copyright Pearson Prentice Hall Cloning Cloning Copyright Pearson Prentice Hall http://resources.edb.gov.hk/biology/english/images/genetics/panda.gif • Researchers hope cloning will enable them to make copies of transgenic animals and help save endangered species. Cloning • Studies suggest that cloned animals may suffer from a number of genetic defects and health problems. – Abnormal gene expression – “old” DNA Copyright Pearson Prentice Hall DNA technology raises important ethical questions • Our new genetic knowledge will affect our lives in many ways • The deciphering of the human genome, in particular, raises profound ethical issues – Many scientists have counseled that we must use the information wisely Figure 12.21A-C Could transgenics harm human health or the environment? • Genetic engineering involves some risks – Possible ecological damage from pollen transfer between GM and wild crops – Pollen from a transgenic variety of corn that contains a pesticide may stunt or kill monarch caterpillars Figure 12.20A, B Insulin-dependent diabetes can now be treated with insulin produced through the use of a) b) c) d) transgenic plants. transgenic animals. transgenic microorganisms. transgenic fungi. Copyright Pearson Prentice Hall Transgenic tobacco plants that glow in the dark were produced by transferring the gene for luciferase from a a) b) c) d) clone. bacterium. firefly. jellyfish. Copyright Pearson Prentice Hall The first mammal to be cloned was a a) b) c) d) sheep. horse. dog. cat. Copyright Pearson Prentice Hall In producing a cloned animal, an egg cell is taken from a female and its nucleus is removed. A body cell is taken from a male. The clone from this experiment will a) look just like the female. b) be genetically identical to the male. c) have a mixture of characteristics from both animals. d) resemble neither the male nor the female. Copyright Pearson Prentice Hall Animals produced by cloning have been shown to a) b) c) d) all be perfectly healthy. suffer from a number of health problems. live longer than uncloned animals. be less intelligent than uncloned animals. Copyright Pearson Prentice Hall