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Found in a Parking Lot… Who is This?. Michael Ibsen, a 17th great-grand-nephew of the king’s older sister, Anne of York, poses with the model of his head.
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Michael Ibsen, a 17th great-grand-nephew of the king’s older sister, Anne of York, poses with the model of his head.
The graph above, from the University of Leicester's website, shows part of a sequence from the DNA of two descendants of Richard III's sister, Anne of York. The two descendants' DNA matches perfectly.
Manipulating DNA Molecular Biology
Do Now • What does “engineering” mean? • What is genetic engineering? • How does it impact human existence?
Making Changes: Genetic Engineering • How To Change DNA • First you have to extract DNA from the cells • How would you do that? • Burst the cell with a hypotonic solution! • Then you have to cut the DNA into small workable sizes • Use restriction enzymes to cut DNA • Restriction enzymes cut at specific codes or pattern
Restriction Enzymes • Very precise • Cuts only at specific sites
My brother Barry and my sister Carrie made blueberry pie for my older brother Harry.
Making Copies Making Copies Making Copies Making Copies • The process is called polymerase chain reaction (PCR) • The DNA is heated to separate the strands • What bonds are being broken? • Hydrogen • A DNA polymerase found in bacteria that can survive high temperatures is used to copy the strands • By heating and cooling over and over again multiple copies are made
Gel Electrophoresis • DNA fragments are separated by size • The gel is porous which allows DNA to move through it • The smaller pieces move faster (and thus further) http://learn.genetics.utah.edu/units/biotech/gel/
Sequencing DNA • DNA is copied several times then is cut with enzymes for every base • Fluorescent dyes are used to mark the bases • The bases are read and the sequence determined ACGT
Recombinant DNA • We can use engineered DNA and recombine these changed pieces into normal DNA • It is spliced in - just like cutting and pasting
Cell Transformation • The incorporation of external DNA into a cell’s DNA • Griffith observed this in his experiments • Plasmids are used to transform cells • Small circular strands of DNA found in bacteria • Naturally help external DNA recombine with the cells DNA
When we use plasmids to transfer genes we also use genetic markers • These markers are genes for antibiotic resistance Only cells that have been transformed can survive antibiotics! A control mechanism
Transformed Bacteria • We can use plasmids to insert human genes into bacteria • Some genes that have been used are • Human growth hormone • Human insulin • The bacteria now produce large amounts of these human enzymes • These enzymes are collected and used to treat related diseases • Human genes produce human enzymes even when transferred into bacteria!
Transforming Plants Cells • Used to create GMOs that are resistant to disease and harvested for food
Pesticide Resistance Protects Corn from Corn-Borer Insect http://www.scq.ubc.ca/plant-breeding-versus-plant-genetics/
Transforming Animals Cells • Some cells are large enough to inject DNA • Bacteria can sometimes be used to insert DNA • Viruses have also been used • These methods have been used to treat genetic diseases - some success • Some genetically modified animals have been created
CONSIDER THIS… • What “cons” should we consider when using genetically modified organisms? • Do the “pros” outweigh the “cons”?