Download who is oj simpson???

WHO IS OJ SIMPSON???
• O. J. Simpson was a Hall of Fame football player
• Running back for the Buffalo Bills (U.S.C)
• Major motion pictures and in television
commercials
• In June, 1994, Simpson was accused of murdering
his ex-wife, Nicole Brown Simpson, and her
companion, Ron Goldman.
• At the trial which took place a year after the deaths,
DNA fingerprinting evidence was presented for the
first time in a major case.
• Blood found of the door of Simpson's Ford Bronco
matched the blood found at the crime scene as
established by DNA testing.
• The same blood was found adjacent to a shoeprint
fitting Simpson's shoe size and on other articles at
the crime scene.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
O.J. Simpson capital murder case,1/95-9/95
•
Odds of blood in Ford Bronco not being R. Goldman’s:
•
•
6.5 billion to 1
Odds of blood on socks in bedroom not being N. Brown-Simpson’s:
•
•
8.5 billion to 1
Odds of blood on glove not being from R. Goldman, N. Brown-Simpson, and O.J. Simpson:
•
•
21.5 billion to 1
Number of people on planet earth:
•
•
Odds of being struck by lightning in the U.S.:
•
•
2.8 million to 1
Odds of winning the Lottery:
•
•
7.1 billion
76 million to 1
Odds of getting killed driving to the gas station to buy a lottery ticket
•
4.5 million to 1
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
DNA Evidence
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Honors Biology: DNA Technology and Society
Figure 12.12B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
14.3 Manipulating DNA
• Cutting, Separating and Reading DNA
• Restriction Enzymes
• Gel Electrophoresis
• Probes
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Enzymes are essential tools in DNA technology
Restriction enzymes (endonucleases)
•
Made by bacteria to cut out foreign DNA
•
cut DNA at specific sequences
– used like molecular scissors
•
Recognition sequences: 4 to 6 bp’s long
•
Some cut and leave “sticky ends”
•
Bacteria methylate A’s and C’s to protect
own DNA from being cut up
•
Ex: EcoR1
DNA ligase
•
used to “paste” DNA fragments together
Restriction enzyme animation
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RESTRICTION ENZYMES aka Molecular Scissors
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Gel electrophoresis sorts DNA fragments by size
• a molecular sieve (jello) to separate chunks of DNA based on size
• restriction enzymes used to chop up DNA into RFLP’s
• RFLP: restriction fragment length polymorphism
• process utilizes negative charge of DNA to move pieces thru the gel
• bigger pieces stay close to origin, smaller pieces move farther
toward the positive end
• result is a DNA fingerprint (bar code) of your specific DNA
pieces…everyone’s DNA will chop up differently fingerprint is unique
RFLP animation
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
The Human Genome Project : a major application
of DNA technology
•
Began in 1990: involved genetic and physical mapping of
chromosomes and DNA sequencing
•
Data provide insight into development, evolution, and diseases
•
Most of the human genome does not consist of genes
•
The haploid human genome contains about 25,000 genes and a huge
amount of noncoding DNA
•
noncoding DNA: repetitive nucleotide sequences (“junk DNA”) and
transposons that can move about within the genome
• repetitive sections found at centromere and at tips of
chromosomes (telomeres) provide chromosome structure
* telomeres have protective function for chromosomes
* significant loss of telomeric DNA quickly leads to cell death.
* abnormally long telomeres are linked to cancer cell immortality
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
The science of genomics compares whole genomes
• The sequencing of many prokaryotic and eukaryotic genomes
• Nonhuman genomes can be compared with the human genome
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
DNA Fingerprinting Activity
• DNA Fingerprinting
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Chapter 15 Genetic Engineering
• 15.1 – Selective Breeding
• Selective Breeding
• Hybridization
• Inbreeding
• Biotechnology
• Bacterial Mutations
• Polyploid Plants
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Selective Breeding: Hybridization and Inbreeding
Selective Breeding: takes advantage of naturally
occurring variations and passes them to next
generation
ex) corn has been highly selected by native
Americans for centuries and changed from a useless
grass to the most productive food crop on the planet.
1. Hybridization: crossing of dissimilar individuals to
get the best of both into the offspring
ex: disease resistance of one plus the crop yield of the
other
2. Inbreeding: the continued breeding of those with
similar characteristics
ex: dog breeds are inbred to keep gene pool constant
for those particular traits unique to that “breed”
**down side: because all are so similar, you increase
the chance that 2 recessive alleles for a disease join.
Now that disease stays in that gene pool and is tuned
over in a high frequency.
(ex: hip problems in labs, arthritis in golden retreivers)
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Q: How can we increase variation in a species?
A: Cause Mutations
1.
Radiation and chemical exposure of bacteria
* most mutations are harmful, but a few
prove beneficial for a particular environment
ex: oil-digesting bacteria
ex: attempts to mutate bacteria to “eat”
radioactive waste and render it stable
ex: attempts to mutate bacteria to
digest metals and clean the
environment of industrial waste
2.
Polyploidism (in plants)
* use chemicals that don’t allow
chromosomes to separate during meiosis 
get a 2N egg or 2N pollen (sperm)
* result? 3N or 4N plant
* new polyploid species are
bigger and stronger than diploid relatives
* ex: bananas and other vital crops
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
15.2 Recombinant DNA
• Southern Blot
• PCR
• Recombinant DNA
• Plasmids
• Transformation
• Genetic Marker
• Transgenic Organisms
• Clone
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
PCR is used to amplify DNA sequences
(PCR) polymerase chain reaction
• used to clone a small
sample of DNA quickly
• produces enough
copies for analysis
• used when DNA source
is scant or impure
• in a few hours, PCR
yields 100 Billion copies
of one gene
PCR animation
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Figure 12.14
Changing DNA
• Early work = Griffith’s experiments on bacterial
transformation (recall from chapter 10)
• A cell takes in DNA from outside the cell and
becomes a part of that organism’s genome
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
BACTERIAL PLASMIDS AND GENE CLONING
Plasmids are used to customize
bacteria
•Plasmids are extra rings of DNA
outside the bacterial nucleoid
•Researchers can insert desired genes
into plasmids, creating recombinant
DNA plasmids (rDNA)
•The new plasmids are inserted
into other bacteria
•If the recombinant bacteria multiply into a
clone, the foreign genes are also copied
•The bacteria can also express the
new gene and make the protein
•
Ex: insulin production
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
real
plasmid
Bacteria are used as:
1. copy machines
(to clone genes)
2. factories
(to make protein of inserted gene)
B
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P
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Figure 12.1
Plasmid DNA Transformation
Fig. 15.10
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Cloning a gene
in a bacterial
plasmid
•
Sometimes a genetic marker
is used to ‘see’ if the bacteria
has accepted the new DNA (a
gene that is resistant to
antibiotics, one that glows, etc.)
Cloning animation
Figure 12.3
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Transgenic Organisms
• Transgenic – containing
genes from other species
• Can be produced by
insertion of recombinant
DNA into the genome of
host organism
• Transforming a Plant Cell
• Possible bc of universal
genetic code
• Can increase food supply
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Transgenic Animals: contain genes from other animals
• Genes from other organisms are inserted into their genomes
• Involves in vitro fertilization and injection of desired gene
directly into fertilized eggs
• Engineered embryos are implanted into a surrogate mother
• Ex: pigs with human cell lines for organ donation
• Ex: chickens produce eggs with additional proteins
Q : Is it ethical? What are the risks?
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
What happens when a GM crops
pass genes for pesticide and
herbicide resistance to weeds?? 
superweeds that would be very
difficult to destroy
Examples of Transgenic Organisms
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To Clone or Not to Clone?
• A clone is an individual created by
asexual reproduction
• genetically identical to a
single parent
• Cloning has many benefits but
evokes just as many concerns
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Nuclear transplantation is used to clone animals
• * Reproductive cloning of nonhuman mammals is useful in
research, agriculture, and medicine
• * Therapeutic cloning produces stem cells which can
perpetuate themselves in culture and give rise to specialized cells
cloning
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stem cell research
Yes, the jokes are FREE!!!!!
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
15.3 Applications of Genetic Engineering
• Health and Medicine
• Gene Therapy
• DNA Microarray
• DNA Fingerprinting
• Forensics
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
GENETICALLY MODIFIED (GM) ORGANISMS
• Recombinant DNA technology is producing new genetic varieties of plants
and animals
Ti plasmid animation
• Use Ti plasmid of Agrobacterium tumefaciens as the vector  GM plant
• ex: soybeans and cotton crops receive bacterial genes to make them
resistant to herbicides and pests
• ex: “golden rice” = rice with a few daffodil genes added.
Rice plant can now make B-carotene, needed for vitamin A production in
humans. Vitamin A deficiency (and resulting blindness) is a serious
problem for ½ of the world who depend on rice as their staple food.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Recombinant cells and organisms can mass-produce
gene products for medicinal and other purposes
1982: Humulin
The first
recombinant drug
made by bacteria
and approved by
the FDA
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Mass-Produced Gene Products cont’d
1.
Bacteria with plasmid: get gene product in large quantity
ex: insulin
2.
S. cerevisiae yeast: eukaryotic cell with plasmids can produce
eukaryotic proteins better
ex: proteins for hepatitis B vaccine
HepB vaccine animation
3.
Mammalian cells: can process large proteins better
ex: Factor 8 (fight hemophilia), TPA (fight heart attacks)
and EPO (fight anemia)
4.
Whole organism: gene is added to genome and the
gene product (protein) is then produced in the organism
ex: human gene into cows to make milk with human protein
ex: human gene into sheep to make milk with a blood protein to fight CF
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Gene Therapy
• Is the alteration of an afflicted
individual’s genes
• Use a harmless recombinant virus as
a vector (deliverer of needed gene)
• Remove bone marrow cells and
treat with recombinant virus
• “infected” cells with injected gene are
put back into patient.
• Patient now has needed gene in
bone marrow cells
•
May one day be used to treat both genetic
diseases and non-genetic disorders.
Unfortunately, progress is slow
Figure 12.13
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
DNA Microarray
• Technique used to study
LOTS of genes at once
and to understand their
activity levels
• ssDNA spots are
attached to a glass slide
(spots contain different
fragments)
• Colored tags are used to
label the source of DNA
• EX. compare cancer
genes with normal
genes
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
RFLP’s used to detect differences in DNA sequences
1
2
• Used in crime scene
investigations to show
guilt or innocence of suspect
• Body fluids left behind are
processed and analyzed through
gel electrophoresis
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
DNA Probes Can Detect Harmful Alleles
• Radioactive
probes can reveal
DNA bands of
interest on a gel
• Used in genetic
screening tests
• Huntington’s
Disease
• Cystic Fibrosis
person I has Huntington’s. Persons II and III
are being tested…results?
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
#3. DNA bands treated to
separate double strands.
Single strands blotted off
onto filter paper.
#4. Blotted paper is
treated with radioactive
probe (complimentary to
gene sequence of disease
causing gene) Probe
attaches to RFLP’s from
original gene …get several
bands
#5. Unattached probe
rinsed off. Photographic
film placed on blot paper.
Radioactivity exposes film,
forms image corresponding
to DNA which base-paired
with probe
Crime Scenes and DNA Evidence
• Many violent crimes go
unsolved for lack of enough
evidence
• If biological fluids are left at
a crime scene, DNA can be
isolated from them
• DNA fingerprinting
determines with near
certainty whether two
samples of DNA are from
the same individual
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Investigator at one
of the crime scenes
(above), Narborough,
England (left)
DNA fingerprinting can help solve crimes, paternity suits
Defendant’s
blood
Blood from
defendant’s clothes
Victim’s
blood
Figure 12.12B
Figure 12.12A
Q: Did he do it?
Fingerprint (12E) activity and Discovery
channel “Forensics” video
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
The Simpsons’
Background information: Homer got into a dispute at a local
establishment. To avoid a standoff, Homer takes his family to his
father’s farm to hide out. We join Homer and his family as they
arrive at the farm.
TOMACCO
Explain, in detail, how this Simpsons’ clip relates to genetic
engineering.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Southern Blot
• Technique for finding specific DNA
sequences using a labeled piece of nucleic
acid as a probe
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings