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Biotechnology. Four hot topics in biotechnology:. DNA Fingerprinting. Genetically modified food. Cloning. Stem Cells. Biotechnology. Biotechnology : the engineering of organisms for useful purposes. A chimera, a mixture of a goat and a sheep. Animal Cloning.
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Biotechnology Four hot topics in biotechnology: DNA Fingerprinting Genetically modified food Cloning Stem Cells
Biotechnology Biotechnology: the engineering of organisms for useful purposes. A chimera, a mixture of a goat and a sheep.
Animal Cloning Megan and Morag, the world’s first cloned mountain sheep.
Why Clone Animals? 1. To answer questions of basic biology 2. For herd improvement 3. For pharmaceutical production 4. To make us happy (e.g. pet cloning) Prometea, the first cloned horse (in foreground) with her identical twin and surrogate mother Stella Cometa.
Utah State University (And Idaho State) First Cloned Mule
An egg is taken from the surrogate mother A needle removes the DNA from the egg cell. An udder cell (or other somatic cell) is taken from the organism being cloned. The “blank” egg cell is fused with the udder cell. Electricity stimulates the fused cell to begin dividing into an embryo. Udder Cells Egg Cell
The First Cloned Pet This is “Carbon Copy”…the first cloned pet. Carbon Copy is not a phenotypic carbon copy of the animal she was cloned from. http://www.jpvpk.gov.my/html/news/archives/English/Feb02%2016B.htm http://drsophiayin.com/blog/entry/cloning-cats-rainbow-and-cc-prove-that-cloning-wont-resurrect-your-pet Rainbow and her clone “cc” (Science (2002) 295:1443)
The First Cloned Pet If they are clones, why aren’t the identical? The genes that controls coat color can be active or inactive in each skin cell. This is a random process. Even though CC has the gene for orange spots, that gene has been “turned off” Read more about these un-identical clones here.
Is Animal Cloning Ethical? The first cloned horse and her surrogate mother/genetic twin. The answer can’t be determined by scientists alone.
Stem Cells A stem cell is a cell that has not yet been assigned a specific function. During development the stem cells become specialized White Blood Cell Nerve Cell Stem Cell Skin Cell
Stem Cells This specialization is terminal. That means that once a cell has been specialized it can only produce more cells like it. White Blood Cell White Blood Cell
Stem Cells Where can you find stem cells? This is a four day old embryo called a blastocyst. Each of these developing cells is a stem cell! One of the best sources for stem cells is an embryo of a developing fetus.
FYI: When stem cells are harvested, the embryo is destroyed and can no longer grow into a fetus
Stem Cells What do scientists do with stem cells? Researchers believe that stem cells can be used to replace damaged tissue caused by: Cancer Multiple Sclerosis Parkinson’s Disease Spinal Damage
Ethical Questions Are these masses of cells a human? If stem cells are taken from these masses, are you destroying life?
More Ethical Dilemmas At what point does an embryo become a human? Is it ethical to use “extra” or “left over” embryos from In Vitro fertilization for stem cell research? If your grandfather developed a disease that could possibly be cured using stem cells, would you donate an embryo?
Stem Cells There ARE other sources for stem cells, but they are believed to be inferior to embryonic stem cells: Bone Marrow Lipid cells
DNA Fingerprinting What are we looking at? The defendant stated that the blood on his clothing was his, was he telling the truth? A DNA fingerprint used in a murder case.
DNA Fingerprinting Different individuals carry different alleles. Most alleles useful for DNA fingerprinting differ on the basis of the number of repetitive DNA sequences they contain.
DNA Fingerprinting DNA can be cut up in pieces of alleles. Each piece is a different size. A DNA fingerprint is made by analyzing the sizes of DNA fragment.
The DNA Fragments Are Separated on the Basis of Size The technique is gel electrophoresis. The pattern of DNA bands is compared between each sample loaded on the gel.
Genetically Modified Foods We genetically modify our food for disease resistance, to change its taste, and to make it grow faster and larger.
Genetically Modified Foods What is the controversy? A branch of government called the “Food and Drug Administration” (FDA) is responsible for determining if a food or drug is “safe” For example, genetically modified salmon: The FDA treats this as an animal drug and not a food. This means they have a very narrow definition of “safe” and do not necessarily run the correct tests on the salmon before we eat it. http://www.sciencemag.org/content/330/6007/1052.full.pdf
Genetically Modified Foods However, many organizations have used what we DON’T KNOW about GM foods to try to stop genetic engineering of foods all together. The “Indian Institute of Science” noted that people have been eating GM corn for more than a decade in several countries, and there have been no related health issues reported. http://www.nature.com/nature/journal/v480/n7377/pdf/480321d.pdf
Methods for Plant Genetic Engineering are Well-Developed and Similar to Those for Animals
Golden rice (yellow) with standard rice (white). Golden Rice is Modified to Provide a Dietary Source of Vitamin A Worldwide, 7% of children suffer vitamin A deficiency, many of them living in regions in which rice is a staple of the diet. However, many of these same regions have banned GM foods
Genetically Modified Crops Genetically Modified Cotton (contains a bacterial gene for pest resistance) Standard Cotton
Biotechnology Let’s summarize: • Four of the most talked about biotechnology efforts are in cloning, stem cell research, DNA fingerprinting, and genetically modified foods. • Advances in biotechnology raise ethical questions that scientists alone cannot answer.