Upload
leslie-charles
View
233
Download
2
Tags:
Embed Size (px)
Citation preview
DNA technology
• Gene cloning• Gene therapy• Biopharmaceuticals• Forensics
– DNA fingerprinting, PCR
• Genomics– Human Genome Project
• Frankenfoods– Genetically modified crops
Recombinant DNA & Plasmids Combining genes from different sources and/or species
• Circular DNA from bacteria = plasmids
• Target DNA recombined in plasmid
• Bacteria rapidly reproduces many clones
How is this possible?
• Enzymes– Used to “cut and paste”– Restriction enzymes
• Cuts DNA into fragments– remember DNA lab
– DNA ligase• Pastes fragments from one
source into another
Biopharmaceuticals• Use recombinant cells to
mass produce proteins– Bacteria– Yeast– Mammalian
• Insulin– Hormone required to
properly process sugars and fats
– Treat diabetes – Now easily produced
by bacteria
• Growth hormone deficiency– Faulty pituitary and
regulation– Had to rely on cadaver
source– Now easily produced
by bacteria
Not always used for good...
• High doses of HGH can cause permanent side effects– As adults normal growth
has stopped so excessive GH can thicken bones and enlarge organs
Forensics
• DNA profiling or DNA fingerprinting
• Requires only small samples (saliva, blood, semen, etc.) left at a crime scene
• Probability up to 1 in a billion
• e.g. O.J. Trial, CSI, Law & Order…
PCR
• Polymerase chain reaction– Used to amplify or
make many DNA copies of a small sample
Genetically modified organisms (GMO)
• Use of recombinant plasmids in agriculture– plants with genetically
desirable traits• herbicide or pesticide resistant
corn & soybean– Decreases chemical
insecticide use– Increases production
• “Golden rice” with beta-carotene
– Required to make vitamin A, which in deficiency causes blindness
Other benefits of GMOs
• Disease resistance– There are many viruses, fungi, bacteria that cause
plant diseases– “Super-shrimp”
• Cold tolerance– Antifreeze gene from cold water fish introduced to
tobacco and potato plants
• Drought tolerance & Salinity tolerance– As populations expand, potential to grow crops in
otherwise inhospitable environments
Where in the world?
Downsides???
• Introduce allergens?
• Pass trans-genes to wild populations?– Pollinator transfer
• R&D is costly– Patents to insure profits
• Patent infringements• Lawsuits• potential for capitalism to
overshadow humanitarian efforts