bellringer what do you know about the following topics? stem cells, genetically modified organisms,...
TRANSCRIPT
Bellringer What do you know
about the following topics? Stem cells, genetically
modified organisms, gene therapy, cloning
Do you think humans have gone too far in terms of “Playing God”?
Test Mistakes
Find 4 mistakes you made on the test
Answer the question correctly, identify and explain the mistake that you made
2.25.14 … Agenda Objective: To genetic tech topics Agenda:
Bellringer: Test Mistakes Notes on Genetic Tech
Homework: N/A
Biotechnology The modification of organisms, cells, and
their molecules to achieve practical benefits
Biotech issues
DNA Fingerprinting Gene Therapy GMOs Cloning Stem Cells
In 1981, Julius Ruffin was sentenced to life in prison for a crime that he did not commit.
In 2003, DNA evidence revealed that he was innocent.
Comparing DNA Patterns
DNA fingerprinting Every person is genetically unique, so DNA
samples can be used to identify (‘fingerprint’) people
DNA Fingerprinting
DNA is unique from person to person DNA is extracted from cells and mixed with
enzymes which cut the DNA into fragments these fragments are exposed to electrical
current and separated by size to leave a unique pattern
1. Unwinding
2. DNA polymerase joins nucleotidesto form new strands
PCR can make billions of copies of DNAThe Polymerase Chain Reaction
A
C
b
G
A
c
B
A
C
b
A
c
B
G Variable number tandem repeat (VNTR)
4 VNTRs 5 VNTRs
A
C
b
A
c
B4 VNTRs 5 VNTRs
Restriction enzymes cut DNA on either side of the region that varies
This produces fragments of different sizes
…GAATTC……CTTAAG…
Gel Electrophoresis (running an electric current through a gel)
DNA fragments are separated as they move through a gel under the influence of an electric field
DNA is negatively charged so it moves towards the positive end
Short fragments of DNA move faster and farther
DNA pieces are separated by size using gel electrophoresis
Which suspect was present at the crime scene?
A. Suspect #1B. Suspect #2C. Suspect #3D. All of the
above.
CrimeScene
#1 #2 #3
DNA FingerprintingPros
DNA is unique from person to person but the same from cell to cell in one person
Paternity and Maternity Criminal Identification and
Forensics Personal Identification Wildlife Management
Cons Invasion of privacy
(ETHICS)
DNA fingerprinting = CSI
What pair of parents is the soldier the child of?
Who is guilty of killing the victim, and where?
Gene Therapy A technique for correcting defective genes responsible
for disease development. A carrier called a vector is used to deliver the
therapeutic gene to the patient. Currently, the most common vector is a virus that has been genetically altered to carry normal human DNA.
Target cells such as the liver or lung cells are infected with the viral vector. The vector then unloads its genetic material containing the therapeutic human gene into the target cell.
The person then uses the gene
Gene TherapyPros
Treatment of a genetic disease for which no treatment is currently available
Potential for life-long treatment from a single injection
Cons Immune response viruses may target the
wrong cells May be inserted into the
wrong place in the DNA may lead to the
development of a tumor
Bellringer Is your DNA totally unique
to you? What is a DNA fingerprint? Some mafia gangster
robbed a bank, and then inexplicably left blood and semen everywhere for CSI to analyze. Based on this DNA fingerprint, who dunnit?
3/26/14
Bellringer: DNA Fingerprint
Finish Biotechnology Intro
Debate and Persuasive Paper
Genetic Engineering: Ethical Issues regarding new technologies
GMOs: Genetically Modified Organisms
Introducing new traits into organisms using recombinant DNA technology.
There are several methods for introducing genes into plants, including: infecting plant cells with plasmids as vectors
carrying the desired gene shooting microscopic pellets containing the gene
directly into the cell.
Genetic Engineering
• Proteins that are made this way:
– Insulin for diabetics
– Clotting factors for hemophiliacs
– Bovine growth hormone
Over half of all food in U.S. contains at least some GM foods
• Modified for herbicide and pest resistance
GMO Crops
Pros Improved Nutritional Quality Pest Resistance Herbicide Resistance Drought Resistance Biopharmaceuticals (getting
plants to make pharmaceuticals)
Cons endangering native
species Monopolization of
GMOs unknown health
risks "genetically
contaminate" wild populations and ecosystems
Taiwan breeds fluorescent green pig
The transgenic pigs, commonly used to study human diseases, would help researchers monitor and trace changes of the tissues during the physical development
Cloning Making an exact copy of an
organism by using its DNA Insert DNA into an ‘empty’
egg, implant it in a surrogate, and a new offspring/clone is born
Reproductive Cloning Production of a fully-developed individual that is genetically identical to the original
Therapeutic Cloning Development of cells or tissues used to treat disease
Cloning The first mammal to be cloned was a sheep
Dolly, 1997
Why are scientists interested in cloning?
To study development To treat diseases
Will someone clone a human?
• Nearly all scientists think it would be unethical
CloningPros
organ transplant propagation of animals facing
extinction produce skin, cartilages, and
bones to save the victims of burns and accidents
produce cells to cure cancer, or repair the retina, or the spinal column
Cons ETHICS Has not been perfected
yet Health risks from
mutation of genes Animal clones have had:
shorter life expectancy liver failure compromised immune
function
tumor growth
Bellringer
Human Genome Project: The sequencing and
locating of all the genes in human DNA
What are benefits of this project you can think of?
Negatives?
Eukaryotic cell
Nucleus
Protein
Genome – an organism’s complete set of DNA
GENOME
CHROMOSOME
GENE
PROTEIN
Insulin
RNA polymeraseRepressor
Cells regulate gene expression, or the types of proteins that are made in that cell: Turned on protein is made Turned off protein is not made
During development, cells with the same DNA gradually express different genes
Cell differentiation
Stem Cell Research
Cells that have the remarkable potential to develop into many different cell types in the body
Can be grown indefinitely in the laboratory Can be used to repair organs/tissues that
won’t on their own, since these cells can become any kind of cell
Embryonic Stem Cells Can differentiate into many adult cell types
Adult Stem Cells Can differentiate into a few adult cell types
Stem Cell Research
Pros Can be used to treat
diseases which currently have no cure
replacement cells and tissues/organs
Cons Come from human
embryos or fetuses ETHICS
Is it ethical to harvest embryonic stem cells from the “extra” embryos created during in vitro fertilization?
Are these masses of cells a human?
Ethical Questions
Stem Cell Research
Genetic Technology Debate & Persuasive Essay
First, rank the following issues from MOST INTERESTED to LEAST INTERESTED
Gene Therapy GMOs Cloning Stem Cells
Hopefully you’ll get one of your top 2 choices
Genetic Technology Debate & Persuasive Essay
Each student will be assigned a topic to begin researching.
Then each student will be assigned what side of the debate they will be defending.
Regardless, you’re researching both sides of the issue which will lead to a well written paper.