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BIOSPHERE
3 PARTS: ATMOSPHERE (air) HYDROSPHERE (water) LITHOSPHERE (crust)
Pic from: http://www.ucar.edu/learn/images/athylibi.gif
The Thin layer of LIFE on the Earth.
CHAPTER 13GENE TECHNOLOGY
http://www.ekac.org/swissprot/swissprot.htmlhttp://www.guardian.co.uk/commentisfree/2008/jan/15/chewonthis
DNA IDENTIFICATION Except for identical twins no two
people are genetically alike .10 %of the human genome varies
between people!! DNA can be used in identifying
human remains, providing evidence in criminal cases, and determining paternity
TECHNOLOGY VOCABULARY
Noncoding DNA – DNA that doesn’t code for a protein “junk” DNA
Polymorphism-variations in the length of “junk” DNA
VNTR- variable number tandem repeats- number of repeats determines what is different
in individuals & this is what forensic scientists look at in DNA profiling
Ex: CACACACACACA-can repeat a few times or many times
STEPS IN DNA IDENTIFICATION
1. Isolate the sample and make copies
2. Cut the DNA into shorter fragments that contain known VNTR’s
3. Sort the DNA by size (use gel electrophoresis)
4. Compare patterns of the unknown DNA sample to a known DNA sample
STEP 1: ISOLATE AND COPY
Polymerase chain reaction – technique used to make copies of DNA fragments
You can make millions of copies
18mp.army.mil
authorjenniferchase.com
STEP 2: CUT DNA INTO SHORTER FRAGMENTS
Restriction enzymes-bacterial proteins that recognize a specific sequence of DNA and cut the DNA in specific sequences
biotechlearn.org.nz
3. SORT THE DNA BY SIZE Fragments of DNA are studied using a
technique called gel electrophoresis Separates molecules according to size &
electrical charge The smaller fragments move faster and
farther than the larger fragments
en.wikipedia.org biology.arizona.edu
4. COMPARE PATTERNS OF KNOWN DNA TO UNKNOWN DNA
Biologists use subtle genetic differences in DNA to identify each individual
baronescience.info
•Accuracy: odds that 2 people will share the same DNA profile are about one in one billion!!
•DNA fingerprinting compares between 5-13 VNTR’s to produce a profile
IMPORTANT VOCABULARY
Genetic engineering-altering the genetic material of cells or organisms to allow them to make new substances
Clone – exact copy of DNA segment, cell, or complete organism
Plasmid – small rings of DNA found naturally in some bacterial cells
Vector – any agent, such as a plasmid or virus that can carry a DNA molecule from 1 organism to another
MAKING RECOMBINANT DNA
Recombinant DNA – when DNA from 2 different organisms is joined
To do this: Insert a gene for an enzyme or hormone into a genome of bacteria or another organism- the organism produces new proteins that it couldn’t before- examples include insulin and HGF
II. HUMAN GENOME PROJECT
A research effort to sequence all 3.3 billion nucleotides of the human genome
Determine locations of every gene on every chromosome!!
bioinformaticonline.com
GOALS FROM WEBSITE HTTP://WWW.ORNL.GOV/SCI/TECHRESOURCES/HUMAN_GENOME/HOME.SHTML
identify all the approximately 20,000-25,000 genes in human DNA
determine the sequences of the 3 billion chemical base pairs that make up human DNA
store this information in databases improve tools for data analysis transfer related technologies to the private
sector address the ethical, legal, and social issues
(ELSI) that may arise from the project.
There are about 8 million single nucleotide polymorphisms (places where individuals differ by only 1 nucleotide – used in DNA fingerprinting)
APPLICATIONS
Discovered specific genes responsible genes responsible for several genetic disorders Researchers can improve diagnoses and
treatments for more than 4,000 disorders
GENETIC ENGINEERING
Medical Applications – gene therapy, cloning, vaccines
B. Agricultural Applications – genetically modified crops
C. Bioethics – the study of ethical issues related to DNA technology
MEDICAL APPLICATIONS
Gene Therapy – introducing a gene into a patients cell to treat a genetic disorder Works best with disorders that result from the
loss of a single protein Ex. Cystic fibrosis, Hemophilia, Sickle Cell Anemia
Steps involved in gene therapy 1. Isolate the functional gene 2. Insert healthy gene into a viral vector 3. Introduce the recombinant virus to the
patient
MR. GREEN GENES (2008)
The glow in the dark cat is the result of a genetic experiment.
Researchers wanted to see if he was a transgenic cat – immune to FIV
http://today.msnbc.msn.com/id/27338236#.T1aQ-TGPUQo
Audubon Center for Research of Endangered Species.
CLONING Began in the 1990’s with cloning
whole organisms such as sheep and mice
Dolly was the first cloned mammal born in 1996 She suffered premature ageing and
disease and died at 6 yrs old possibly from having short telomeres.
randomworldofjen.blogspot.com
CLONING – HOW IT WORKS1. Egg has nucleus(with its DNA)
removed
2. Cell from organism to be cloned, such as a skin cell, is collected.
3. Empty egg & whole skin cell are placed close together & electric shocked, which makes them fuse
together.
4. The new cell contains DNA from only
1 cell (the skin cell, not the egg) & is grown
It becomes a new baby.
AGRICULTURAL APPLICATIONS
Develop new strains of plants called genetically modified (GM) crops
Increase the amount produced and improve nutrition In Asia researchers added genes to rice to
over come the iron deficiencies
FIRST GM FOOD
•The first commercially grown genetically modified food crop, a tomato, was made more resistant to rotting, by adding a
gene.•1994- Approved by FDA –decided it did not constitute a health hazard, and did not need special labeling. Calgene was allowed to release it into the market. Welcomed by consumers who purchased the fruit at two to five times the price of standard tomatoes. Company bought by Monsanto in 1995.
Monsanto Company is a multinational agricultural biotechnology corporation & is the world's leading producer of the herbicide Roundup. Monsanto is also by far the leading producer of genetically engineered (GE) seed, holding 70%–100% market share for various crops.
GM MILK COWS
• Scientists introduced a new gene into milk cows that could get them to produce human milk•Healthier alternative for formula?
FISHY STRAWBERRIES
Flounder is a fish that can withstand icy cold temperatures. Scientists took the gene in the fish thatProduces an antifreeze & inserted it into a plasmid of a bacterium The bacterium infected the strawberry & the flounder antifreeze gene entered the strawberry’s DNA The new GM strawberry cells are grown Into new plants that have strawberries which make a protein that keeps the fruit from frost damage.
floundergigging.com
GM MOSQUITOS
Stop mosquito born diseases like malaria buy creating insects that are less infectious
Trying to get them released in the Key West to help eradicate dengue fever and the mosquitos that spread it
FEATHERLESS CHICKEN
In Israel scientists have discovered a way to make a more convenient type chicken – one that’s easier to process
Grows faster because it doesn’t have to use energy to create feathers
Only lives in warmer climates
http://oddanimals.com/featherless-chicken/
ETHICAL ISSUES Is the food safe to eat? Is the food harmful to the
environment? What are your thoughts on gene
therapy? Cloning of human embryos?Decisions must be made by both
scientists and the public