Download Human Genome Project, Stem Cells and Cloning

Genetic Engineering
II. Genetic engineering:
Changing an organism’s
DNA to make it more
beneficial to humans
Genetic Engineering, cont.
A.
Recombinant DNA: DNA made from two
separate species
1.
B.
A gene from one organism is “recombined”
with another organisms DNA.
Transgenic Organism: any organism that
contains recombinant DNA.
a.
These new gene combinations could
never be possible in nature
1.Transgenic Plants
Researchers isolate a gene from an organism that has
the trait they want to give to a plant.
and cells are grown
Just for Fun?- a glowing tobacco plant
http://archives.cbc.ca/IDD-1-75-1597/science_technology/genetically_modified_food/
What’s Next on Your Plate?
What genes do we
want them to have?
•Insect, Herbicide, and
Fungal resistance
•Drought resistance
•Product quality
•Longer Shelf Life
(Flavr Savr Tomato)
Transgenic Organisms:
Plants
Example: Rice plants and daffodils can not
cross pollinate with each other in nature.
The rice on the right is
called Golden
Rice.
Its genome
contains the gene for
producing vitamin A
from daffodils.
This rice is healthier
for people who do not
get enough vitamin A
in their diets.
Transgenic Organisms: Animals
Animals are now being produced with genes that
increase milk production and muscle mass (meat).
Problem: unhealthy; legs cannot support weight
3. Transgenic Organisms: Bacteria
Used to produce important
medicines:
a.
Insulin for diabetics
b. Human
growth hormone
(HGH) to treat pituitary
dwarfism
c.
Bacteria cultures
Anticoagulants for (for
treating heart attack patients)
Insulin
Human Genome
Project
•
A genome is an
organism’s complete set of
DNA
•
Project began in 1990;
Completed in 2003
Coordinated by National
Institutes of Health (NIH) &
U.S. Department of Energy
(DOE)
•
What is the Human Genome Project (HGP)?
Goals of HGP
1. Reading and determining the
sequence of the 3 billion base pairs
in the human genome.
2. Locating and identifying all genes in
the human genome which there is
about 30,000
3. Storing information into databases
that are accessible to the public
4. Analyzing and addressing ethical,
legal, & social issues involved in
using this information
Benefits of the Human Genome Project
1.
2.
3.
4.
We have located many diseased
genes and genetic tests have
been created.
Researching bacteria genomes
furthered research for fuel &
environmental clean-up
Improved technology for DNA
forensic science
Other sequences completed for E.
coli, yeast, simple round worm,
fruit fly, rat & chimpanzee (model
organisms for studying how similar
genes work in humans.)
Maps of chromosomes # 13 & #
17; show the location of BRCA 2
& BRCA 1 – breast cancer genes.
DNA Fingerprinting/Electrophoresis
DNA fingerprinting: tool used by forensics scientists to
identify a person using DNA.
How it Works:
1.
2.
A sample of the person’s DNA is taken from blood,
semen, bone, or hair.
DNA fragments are cut – Restriction enzymes cut DNA
at specific sequences. Useful to divide DNA into
manageable fragments.
Electrophoresis
3.
4.
5.
6.
7.
8.
DNA fragments are separated based on size and
charge.
Phosphate groups are negatively charged
DNA is placed into a gel & connected to an electric
current
DNA moves through the gel toward + pole; shortest
lengths move the fastest & longest lengths move the
slowest.
A characteristic banding pattern is produced and a
photograph is taken
The banding pattern is unique for each person –
thus called a DNA fingerprint
Electrophoresis
15
Electrophoresis
16
DNA Fingerprints
Was any of the victims blood
on the defendants clothing?
Which dog was probably
the culprit (dog that bit
the person)?
How Cloning Occurs in Nature
Clone: an organism that is
genetically identical to
another organism
a. All of the genes are the
same (identical)
2. Examples of cloning that
occurs in nature
a. Reproduction in bacteria
& sponges (asexual)
b. Identical twins are
natural clones
1.
tadpoles.
Briggs and King Investigation
Cultured adult skin cells
Tadpole-gut epithelial cells
Destruction of DNA
in the nucleus of an
unfertilized egg with
ultraviolet radiation
Transfer of nucleus
into egg
Removal of nucleus from
either cell source
Which conclusion is supported by the data from this investigation?
Tadpole
Bacteria and Plant Cloning is Easy
1.
Cloning of transgenic
bacteria creates many
“living factories” used
to make insulin &
other drugs
2. Cloning of transgenic
plants to insure
genetics are intact for
the next generation.
Bacteria that contain genes
for digesting oil can be
used to clean up oil spills.
Animal Cloning is difficult
and controversial
Dolly: First
cloned animal
Also called Reproductive Cloning
What are Stem Cells &
Why Do Scientists Want Them?
1.
Stem cells:
undefined cells that
reproduce continuously
& can develop into any
type of cells or tissues
(link)
2. The hope is to be able
to produce tissue &
organs for transplants
Stem cell technology
can help those who wait
for organ transplants.
Where do we get Stem Cells?
a)
b)
Embryonic Stem cells are most easily obtained
from embryos and umbilical cords. (work best)
They are pluripotent.
Adult Stem cells are found in bone marrow and
skin.