Genetic Engineering & Biotechnology What we can do with genes Read pages 319-321 in your textbook and fill in packet as you proceed

Genetic Engineering & Biotechnology The combination of biology and technology has been making many products better for many years.. such as bread, cheese, and yogurt by using the best ingredients to make the best products. This brings about…. VARIATION !!

Selective Breeding (aka: Genetic Modification) Humans select animals or plants with desirable (beneficial) traits and breed them This ensures that many of the offspring will have desirable traits from both parents This is how we have so many breeds of dogs, horses, cats and foods! This is also how we have certain fruits and vegetables with certain traits – these are known as genetically modified foods ( or GMO’s) Ex: meat products have been bred to contain less fat fruits and vegetables have been selectively bred to be larger, sweeter, hardier, and even juicier, and resistant to fungus infections and temperature changes. Does NOT involve actually changing DNA!

What is Genetic Engineering Intro video: https://www.youtube.com/watch?v=3IsQ92KiBwM Technology that humans use to alter DNA or study DNA Examples: DNA Fingerprinting (aka: Gel Electrophoresis) Used in paternity testing Used as evidence in criminal cases DNA Recombination (aka: Recombinant DNA) Inserting a gene into bacterial DNA Bacteria will then construct the protein coded for in that DNA

Restriction Enzymes Let’s watch https://www.youtube.com/watch?v=8rXizmLjegI Special enzymes that recognize certain DNA bases and then actually cut (splice) the DNA at that location Used in DNA Fingerprinting and DNA Recombination EXAMPLE: EcoRI recognizes GAATTC Will cut at this spot between the G and A Creates STICKY ENDS (single strands of DNA) that can bind to new DNA

Types of Genetic Engineering 1.Gel Electrophoresis Separates DNA into different banding patterns based on NUMBER OF BASES IN EACH CUT STRAND DNA is cut up using a restriction enzyme This leaves DNA strands of different sizes CHARGE OF DNA DNA is negatively (-) charged, so it will move towards a positive charge DNA separates due to opposite charge at one end of chamber and how heavy it is Makes a “finger-print” Let’s See!

Parents will have similar banding to their children and vice-versa - Paternity tests It is important to remember that the child’s DNA came from both of the parents……50% from mom; 50% from dad…and the DNA fingerprint should reflect this. Animation: Let’s See!

2. Recombinant DNA Technology Inserting genes from one organism into a circular piece of bacterial DNA called a plasmid Ex: Inserting human insulin gene into bacterium; bacterium will now make insulin for Diabetics Overview: https://www.youtube.com/watch?v=BK12dQq4sJw&ebc=ANyPxKrH9M65_uBV92KppbTvXn5l4kc20MOzVBkoQZDL40bPKKxC43uSMFYlyxya5lqirodfEKUgPp9bNu0M_xJWd4dGlEXFtQ

cells will replicate (clone) Recombining DNA cells will replicate (clone) Uses: To make insulin & Growth hormone Bacteria can clean up toxic waste (oil spills) Proteins are used to dissolve blood clots for heart therapy

Steps for causing bacteria to make human insulin by Recombinant technology: Cut out insulin gene from human DNA using a restriction enzyme Cut open bacterial plasmid using same restriction enzyme Combine cut plasmids with many copies of human gene Several plasmids will “accept” human gene These plasmids now have the ability to make human insulin This is a cheaper way to obtain insulin because it can be produced in greater amounts & there are smaller risks of side effects since the gene making the insulin is a human gene.

Diagram of Recombinant DNA Clones of bacterial cells

Benefits of Genetic Engineering Making large amounts of a human protein, such as insulin Finding cures by altering DNA… Gene therapy DNA Fingerprinting has helped us to see how similar certain organisms are (common ancestry) Alter DNA in plants to make them resistant to certain diseases Paternity tests. Video 3:07: https://www.youtube.com/watch?v=TpmNfv1jKuA

NOVA: The Killer’sTrail (4:45) http://www. pbs Questions for Discussion How was DNA evidence used to prove that Dr. Sam Sheppard did not murder his wife? Why wasn't this evidence used when the case first went to court? Why do you think the DQA1 test was chosen for DNA analysis in this case, instead of another, more powerful genetic test? If the blood trail left at the murder scene wasn't Marilyn's or Sam's, whose blood might it have been? If you were a juror on this trial, would you be convinced by the DNA evidence?