Download The Good, the bad and the ugly of Genetic Engineering

The Good, the bad and the
ugly of Genetic Engineering
• Genetic engineering
–Scientists change the DNA code
of an organism in order to:
•Make transgenic organisms
•Clone an organism
Transgenic Organisms
• Organisms
which have a
gene from
another
organism in
their DNA
Practical applications
• Plants with “insecticide”
genes
Practical applications
• Cows with
extra copies
of growth
hormones
Practical applications
• Bacteria that
make human
insulin
protein for
diabetics
Practical applications?
• Cool Glow-in-the-dark Mice!!
How?
• Jelly Fish have
a protein called
GFP (Green
fluorescent
protein)
• Gives them that
“glow”
How?
• So… They
must have a
gene (DNA)
that has the
info to make
GFP
GFP Gene (DNA)
Transcription
mRNA transcribed from GFP Gene
Translation
GFP Protein = glowing jelly fish
How?
• What makes us different is What
genes we have not how we make
the proteins!!!
• So all you need to do is give an
organism a new gene and it will be
able to make the protein!
How?
Jelly fish nucleus with GFP
gene
Remove GFP
gene
Mouse nucleus without
GFP gene
Add GFP
gene
Glowing Mice
GFP protein
made
Mouse nucleus
with GFP gene
Insulin made by bacteria
• Diabetes: dysfunctional Insulin
gene; no or low amounts of insulin
protein made
–Means we can’t regulate blood
sugar levels
– we can force bacteria to make
insulin for us
Insulin made by bacteria
• Same process: Tell me how!
1.Find healthy insulin gene in
human
2.Cut it out and insert it in
bacteria
3.Bacteria then MAKE human
insulin even though they have
no use for it!
4.We extract the insulin from
bacteria and use it in injections
Cloning
• Creating an
organism that
is genetically
identical to its
only parent.
Cloning
• Mammals usually mix info from
two parents
• In cloning all the chromosomes of
the baby come from 1 parent.
Sheep 1 Take 1 body
cell (udder)
Sheep 2
Take 1 egg
cell
Extract
Nucleus
Remove
nucleus
Inject
nucleus
into Egg
Zap to
stimulate
cell
division
Implant
egg into
surrogate
sheep
(sheep 3)
Wait for Dolly to be
born
Which sheep is Dolly identical to??
Why?
Which sheep have to be female?
Snuppy: cloned Afghan Hound
Genetic Testing
Checking a fetus to determine if
the baby has any disease.
- Cystic fibrosis
- Tay Sach’s Disease
- Down Syndrome
Genetic Testing
• Done BEFORE birth
• Can detect two kinds of mutations
–Chromosomal: easily visible, major
mutations
–Gene mutations: checking for mutated
gene; must know what you are looking
for!
Amniocentesis
Amniocentesis
Extracting amniotic fluid from
womb
Contains cells from fetus
DNA or protein can be isolated
and examined
Can check for:
1.Mutations in certain genes
(must be looking for
something specific)
2.Chromosome abnormalities
3.Abnormal protein levels
DNA finger printing
• Used to compare two people’s
DNA
• Used in paternity cases
• Used for crime scene analysis
DNA finger printing
DNA finger printing
• Based on the idea that
EVERYONE’s DNA is unique,
like a fingerprint
• BUT related individuals will have
more similarities
How to do a DNA fingerprint
• Get a sample of DNA and digest it
with restriction enzymes
– restriction enzymes cut DNA at
specific sequences.
–For example: EcoRI cuts DNA
every time it sees the sequence
GAATTC
How to do a DNA fingerprint
• If everyone’s DNA is unique, the
enzyme will cut each persons
DNA differently
• Example:
• TCATGAATTCATTGCCGAATTCCGTGAATCCAGAATTCGGACTA
• TCATGAAGTCATTGCCGAATTCCGTGAATCCAGACTTCGGACTA
How to do a DNA fingerprint
• Run cut up DNA on through
electrophoresis
• Click here for animation
How to do a DNA fingerprint
• Small pieces travel fast and move
further down the gel slab.
• Large pieces move slower and
stay closer to the injection point.