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What is it? Selective breeding among live stock and even dogs have been around since the beginning of time. Using microbes to make food and drinks Charles Darwin 1809-1882 natural selection Gregor Mendel 1822-1884 genetics (pea plants) Selective breeding has been around since the beginning of time Humans have selected particular traits and bred organisms to have these traits Don’t we as humans use selective breeding when selecting our mates? Complete The Genetic Technology worksheet front and back The driving force behind DNA technology we have today. 13 yr long research project completed in 2003 where scientist from around the world tried to identify the 20,000-25,000 genes in the human DNA and find the sequences of the 3 billion chemical base pairs Directors of the HGP are hoping that the information gained will help make advances in biotechnology fields. At least 350 biotechnology-based products resulting from the Human Genome Project are currently in clinical trials. http://www.ornl.gov/sci/techresources/Human_Genome/project/timeline.shtml Agriculture 2. Medicinal 3. Forensics 1. Biotechnology and Agriculture http://www.youtube.com/watch?v=qn52Ed1q4rk Genetic Engineering The process of altering the genetic material of cells or organisms to allow them to make new substances. We can do this because DNA is the same from One organism to nextJust a little different order of bases. GMO – genetically modified organism Organisms that have acquired one or more genes artificially Transgenic organisms – organisms that have acquired a gene from another species or organism ex – “super mice” in 1980’s used this in mice so that they could produce a human protein needed for clotting. Biotechnology and food Videos: Cons: http://www.youtube.com/watch?v=1H9WZGKQeYg Pros: http://www.youtube.com/watch?v=cit1LBHThy4 Healthier farm animals Pest resistant plants – so grow more food Temperature, drought resistant, other environmental conditions allow us to grow food where we couldn’t before creating greater genetic diversity in different regions. May have an increase in nutrient value Ex. India – 1992- salinity resistant crops (rice / wheat) has allowed people to grow these in areas that would not normally sustain crops. Ex. Golden rice – transgenic variety created with more beta carotin that could help prevent vitamin A deficiencies that lead blindness in poorer nations New allergies may develop with these plants Pollen from GMO’s can spread to wild species and change their genetics Unpredictable health effects – only been around since 1990’s so we do not know long term effects yet Insufficient government regulation – GMO’s are not mandatory to label in grocery stores – yet May create unwanted effects in soil or surrounding water supplies (ground water) 1. Gene therapy Alteration of afflicted individual’s genes for therapeutic reasons. Try to supplement or replace a defective gene causing the disease by inserting a normal allele into cells of tissues that have the disorder. For this to be permanent, the allele would have to be transferred into cells and multiply throughout life. They are trying to a achieve this for blood and immune disorders. Using bone marrow cells which contain stem cells for all blood products and immune system. Currently being used to cure genetic disorders Specific DNA sequences are inserted to try to replace fully or absent genes so that gene expression can occur The most effective way to is to using viruses to insert the gene sequences into cells. Why viruses? Any ideas? All viruses naturally insert their genetic material into their host cell as part of the replication cycle http://www.youtube.com/watch?v=imL1Zmi3mWk 2. Diagnose Disease: DNA technology used today to diagnose diseases even before birth. 3. Vaccines A mutant of the pathogen (virus / bacteria) used to stimulate our immune system to create defense against the pathogen Some are genetically modified to be better. Genetically altered crops are now grown that can synthesize certain vaccines and eaten by Gene therapy different ways to fight cancer: Inject cancer cells with special genes that make the tumor more receptive to cancer drugs Place multi drug resistant (MDR) genes into the bone marrow to make stem cells more immune to side effects of anticancer drugs. (this preserves more red blood cells for the patient and they are less tired as they go through treatment) Recent research is looking a genetically altering a person’s T cells (ones that give us immune memory) to be cancer specific. Find and recognize cancer and kill it. The good thing about this is that it should last a lifetime due to the “immune memory” of the T cells. Complete DNA Medicine worksheet Read and complete questions about Genetic Testing Read Scientific American article: Gene-Therapy Successes Spur Hope for Embattled Field By Erica Check Hayden http://www.scientificamerican.com/article/gene-therapysuccesses-spur-hope-for-field/ Scientific analysis of evidence from a crime scent to be used in investigations or court of law 1. DNA profiling; Can get DNA from any body fluid, small pieces of tissue, hair, etc… left at the crime scene used to prove paternity Used to identify victim of a crime Ex. World trade center nearly ½ of victims identified by DNA analysis Get DNA fingerprint activity from Lambert Therapeutic hormones such as insulin and human growth hormone are made by modified bacteria. Until now, insulin was recovered from slaughtered pigs and cattle. Now can genetically modify bacteria to produce human insulin. In past HGH recovered from cadavers, now bacteria with modified DNA fragments chemically synthesize HGH to help with dwarfism or other height deficits. How Genetic Engineering Works: Recombinant DNA technology When DNA from two different organisms is joined 1) Isolate the desired DNA and plasmid Plasmid small rings of DNA 2 ) A restriction Enzyme is used o cut the DNA into fragments 3) Sticky ends hold the plasmid and DNA together until enzyme DNA ligase joins them 4) The recombinant bacterium is inserted into a host bacterium 5) The bacterium then reproduces, the desired DNA is identified using a probe Probe – a strand of RNA labeled with a radioactive element or fluorescent dye Gene Splicing The process in which fragments of DNA from one or more different organisms are combined to form recombinant DNA http://www.youtube.com/watch?v=rjqaPSWAYY8 Take a look at the virtual lab For homework complete the lab and print your results Need to an example the works http://glencoe.mcgrawhill.com/sites/dl/free/0078759864/383937/BL_22.html Process of producing a genetically identical copy of a living organism. Occurs naturally in bacteria during asexual reproduction Types of artificial cloning 1. Gene cloning 2. Reproductive cloning 3. Therapeutic cloning Copies of genes or segments of DNA Used by scientists to make copies of genes they wish to study Process: Isolate DNA from organism Isolated DNA is cut at the gene you want (by enzymes) and creates “sticky ends” This gene can then be “glued” into plasmids of a bacteria or virus After gene is inserted the bacteriais allowed to multiply and each time it multiplies, the gene they would like to study also multiplies. They now have multiple copies of this gene to work with. Copies an entire organism Process: Remove somatic cell (skin cell) from an animal being cloned Transfer the DNA of the somatic cell into an egg (DNA removed from egg) Shock it with electricity to start dividing The egg is allowed to develop and then implanted into the womb of a surrogate mother. Cloned animals may be used for testing new drugs or treatments Allows a uniform response because they are identical Build endangered animals Bring back extinct animals Clone pets Creating a cloned embryo for sole purposes of making embryonic stem cells These cells can be used in experiments to understand diseases and develop new treatments Philosophical Issue: Stem cells come from blastocysts (embryonic stem cells 5 days after the cells start to divide). Cells harvested from cloned embryo, which results in the destruction of embryo.