Download Biotechnology

Genetic Technology
and Ethics
What can we do and what should
we do with DNA knowledge?
A. Human Genome Project
•
•
Began in U.S. in 1990, finished in 2003
Main goals:
1. Identify and map all the genes in human
DNA (20,000 – 25,000)
2. Determine the
base sequence of
the 3 billion bases
that make up
human DNA
Modern Sequencing
3. Store this info in
databases
4. Address ethical
issues
– Main benefits:
1.
Determining whether or not a person carries a
gene for a genetic condition or has the
genetic condition
Test for sickle cell anemia
2. development of gene therapy (insertion
of normal genes into cells to treat
genetic diseases)
B. Gene Therapy
• Some genetic diseases
are caused by a
defective gene
• A normal piece of DNA
can be made in lab and
inserted into a vector
(something that will
deliver the normal DNA
to the person’s cells)
• Many times, a virus
shell is used as the
vector
• The virus “infects” the
person’s cells,
injecting the corrected
DNA.
• Cell now uses
corrected DNA to
carry out its normal
functions.
• Cystic fibrosis is
treated this way.
C. DNA Fingerprinting
-
gel electrophoresis is used to separate
DNA fragments based on their size
fragments are then used to compare
samples
-
used in criminal cases and paternity
cases
Electrophoresis use in forensics
• Evidence from murder trial
– Do you think suspect is guilty?
blood sample 1 from crime scene
blood sample 2 from crime scene
blood sample 3 from crime scene
“standard”
blood sample from suspect
OJ Simpson
blood sample from victim 1
N Brown
blood sample from victim 2
R Goldman
“standard”
Genetic Technology
and Ethics
What can we do and what should
we do with DNA knowledge?
Steps of Gel Electrophoresis
GEL ELECTROPHORESIS – technique that
uses electricity to separate DNA fragments
based on their size (leads to a “DNA
fingerprint”)
1. Isolate DNA and purify from cells (skin, saliva,
blood, semen, etc.).
2.Cut DNA into pieces using RESTRICTION
ENZYMES.
3.Prepare gel.
4.Load DNA into wells using micropipette.
5.Hook gel up to a power supply.
6.DNA will move toward (+) end. Smallest
pieces move faster/farther. Observe and
analyze bands.
http://learn.genetics.utah.edu/content/labs/gel/
D. Transgenic Organisms (a.k.a. genetically
modified organisms – GMOs)
- organisms that contain foreign DNA
- made by recombinant DNA technology
Examples of GMOs
• Glowing tobacco plant
• Fishberries
Glowing dog
Examples of GMOs
• Bacteria that
produce human
insulin
– Using bacterial
transformation
• Pest-resistant
plants
E. Bacterial Transformation
A plasmid is cut with a
restriction enzyme
(A plasmid is a small,
circular piece of DNA
often found in
bacteria.)
The human gene (ex.
insulin) is inserted into
the plasmid.
E. Bacterial Transformation
The plasmid is put into
bacteria.
As the bacteria
reproduces, the human
gene is cloned (more
copies are made).
As the bacteria makes
its own proteins, it also
makes human protein.
F. Stem Cell Research
• stem cells – cells of humans that can develop
into different cell types
• 2 kinds: embryonic and adult
• some researchers believe that they can be
a source of replacement cells to treat
disorders (ex. Parkinson’s disease and
burn injuries)
Embryonic stem cells
Adult stem cells
G. Cloning
• Creating an identical
copy of DNA, a cell,
or an organism
• An adult cell is fused
with an empty egg
and implanted into a
female’s uterus
• Problems exist with
this technology:
using “old” DNA
Ethical/Legal/Social Issues
• Who should have access to a person’s info?
• Who owns/controls genetic info?
• Will knowing about a genetic disease increase the rate of
abortions?
• How reliable is genetic testing?
• Should parents be required to treat a child that has a
genetic disease?
• Will genetic engineering lead to another “class” of people?
• Where is the line between medical treatment and
enhancement?
• Are GMO’s safe for people and the environment?
• Does embryonic stem cell research kill babies or simply use
human tissue for the good of mankind?
• Should people be allowed to choose the trait of their child?
Steps of Gel Electrophoresis
GEL ELECTROPHORESIS – technique that
uses electricity to separate DNA fragments
based on their size (leads to a “DNA
fingerprint”)
1. Isolate DNA and purify from cells (skin, saliva,
blood, semen, etc.).
2.Cut DNA into pieces using RESTRICTION
ENZYMES.
3.Prepare gel.
4.Load DNA into wells using micropipette.
5.Hook gel up to a power supply.
6.DNA will move toward (+) end. Smallest
pieces move faster/farther. Observe and
analyze bands.
http://learn.genetics.utah.edu/content/labs/gel/