Download Biotechnology Notes

• What are mutations?
• What are Genetic disorders?
• Trivia tidbit: A tobacco plant has the ability to
glow! How so?
• Can humans glow?
• What are transgenic organisms?
Human Genetics-biotechnology
Vocabulary
• Recombinant DNA DNA that has been genetically
modified by connecting DNA fragments from
multiple sources
• Host organism you are obtaining the gene from
• Vector organism such as a bacteria, you are going
to use to put the recombinant DNA into the organism
you are trying to change
• Plasmid DNA or “chromosome” of a bacteria
• Restriction Enzyme bacterial proteins that have
the ability to cut both strands of DNA at specific
points called restriction sites
Biotechnology
• Biotechnology the use of technology to
manipulate or change life in some manner
– The only way to do this is through changing genes
somehow
• Can occur in many different ways.
–
–
–
–
–
Gene manipulation and DNA recombination
Gene Therapy
Cloning
Stem Cells
Selective breeding and hybridization
Process of manipulating genes
1. Choose an organism to change, and one to obtain the
gene from (host)
2. Choose a bacterial vector that will transform the
gene incorporate gene into its own DNA
3. Gene Splicing Cleave (cut) the pieces of DNA of
interest from the host organism restriction enzyme“cleaves”
4. Isolate the gene located in the pieces of DNA in the
host
5. Insert the gene into bacterial vector DNA
(recombinant DNA)
6. Expose the vector to the organism you are trying to
change
7. Organism must “take up” recombinant DNA
Crystal Jellyfish
Genetic Engineering
• Scientists alter genes of an
organism
– Usually done by Inserting
DNA from one organism
into another
– DNA that has been
genetically modified is
called recombinant DNA
– Organisms with
recombinant DNA are
called genetically
modified organisms
(GMO) or transgenic
organisms
Using Restriction enzymes to make
recombinant DNA
• Restriction enzymes are chemical catalysts that “cut”
DNA molecules at specific locations in order to obtain
certain genes
– Can be used for genetic manipulation or DNA cloning
• Each Restriction enzyme is specific to a specific
restriction site
• They are cut into a specific pattern allowing there to be
sticky ends
– These sticky ends can form hydrogen bonds with other sticky
ends creating a whole piece of DNA with the potenetial for
them being from different sources
Cloning a Eukaryotic gene in a
bacterial plasmid
• Works the same was as making recombinant DNA
with one exception:
• You obtain a piece of DNA from a bacteria, this is
called the cloning vector
– Use a restriction enzyme to produce sticky ends
• You obtain genes from a human cell
• You then expose the human pieces of DNA into the
bacterial cell
• Use the enzyme DNA ligase to “glue” the pieces back
together
• Then you place the bacterial DNA back into the
bacteria
Transgenic organisms
• http://www.youtube.com/watch?v=ujZHrR1m
ro8&feature=player_detailpage
Applications for gene manipulation
• Transgenic bacteria in agriculture
• Transgenic bacteria in Industry
• Transgenic bacteria in Medicine
• Genetically engineered food
• Transgenic plants and animals
Transgenic bacteria in agriculture
• Once species of bacteria have been used
successfully on agricultural crops already
• Specific bacteria naturally occurs on
strawberry plants that promotes frost damage
in strawberries because bacteria has ice
crystals that form around specific protein
– Scientists have been able to isolate the gene for
this protein, and prevent frost damage
– This saves farmers money, provides jobs to
scientists who research and develop this type of
transgenic bacteria, and provides higher quality
and quantity of strawberries
Papaya engineering
• Papayas in Hawaii were threatened by papaya
ringspot virus.
• Scientists in Hawaii isolated the gene in the
virus that makes it immune to itself, then
implanted that gene into new papaya seeds,
and allowed the seeds to reproduce creating
new papaya trees that are resistant to the
papaya ringspot virus
• 1999, the first successful papaya tree
produced, now, ¾ of all Hawaiian papayas are
genetically modified
• Cool fruits:
– pluot
– Lemato
– Tangelo
– Diabetes fighting
lettuce
– Colorful carrots
• We have the
technology to
engineer almost
any food
Transgenic bacteria in Industry
• Scientists have been able to engineer bacteria
to be able to break down harmful pollutants
into harmless chemicals
– Helps environment and provides jobs
• Ex: There is a specific bacteria that naturally
breaks down oil based compounds.
– Scientists genetically engineered bacteria to break
down oil at a much faster pace, and with better
results
Transgenic bacteria in medicine
(“Pharming”)
• Pharmaceutical companies have developed the
widespread use of specific molecules-made by
transgenic bacteria that help to treat human diseases
• Ex:
Human Growth Hormone-given to individuals suffering
from dwarfism
– Chemotherapy drug Interferon to treat cancer
– Insulin to treat diabetes
– Artificial sweeteners are usually made from transgenic
bacteria that produce phenylalanine
– Many treatments for genetic diseases re now being
produced by genetic engineering
Genetically modified foods
• http://www.youtube.com/watch?feature=play
er_detailpage&v=FTfuAbzAeB8
Transgenic plants
• Glowing tobacco
• Plants and animals are much harder to engineer,
because they do not contain plasmids What
are they again?
• Plants
– Difficult to engineer, due to thick cell wall
– Must use artificial vectors such as a gene gun or a
micropipette in other words, they must be done in
a lab and not in nature
– Main purpose to be able to resist herbicides,
produce their own pesticides, or to increase their crop
production
Blue roses
Transgenic animals
• Animals usually will not accept a bacterial plasmid as a
vector, so manual engineering with a gene gun or a
pipette are used when possible
• Manipulated genes are inserted into unfertilized eggs
• Egg gets fertilized and transgenic traits or properties
are expressed
• Uses with livestock-placing human proteins into
livestock so they produce milk with these proteins
already in them
– Ex: There is a protein that dissolves blood clots
transgenic goats have the protein in their milk, so if person
drinks milk, they can dissolve blood clots
• Not very far in development
– Still a very young field
– Ethical issues
Green Florescence protein
Human Genome Project
• In 2000 scientists from 6 countries all
worked together and figured out the “book of
life”
• Wanted to “map out” all nucleotides or bases
that give the template for a human
• Achieved a blueprint of the whole sequence of
bases for humans
• Genomics study of entire genomes
– Study of all bases in an entire organism
Surprise findings
• Humans have few genes
– Scientists thought 120,000 genes
– Reality25,000 genes
• Most DNA is non-coding less than 2% actually
codes for traits
• We share majority of our DNA with other species
– 50% same as a fly, 75% same as dog, 30% same as
banana, and 98% same as chimp
• We all share about 99.9% of our DNA with each
other
Manipulating bodies and development
• In lab=Cloning process used to create
identical DNA fragments, cells, or whole
organisms
• In nature=asexual reproduction
Cloning
• When you clone an old organism, the newly
formed organism’s DNA will have the same age as
the organism.
– New organism has all the mutations that have
occurred in old organism
– Ex: Baby sheep would have old DNA but still be young
and a baby
– Effects:
•
•
•
•
•
•
Increased aging rate
Increased mutations
Shorter life span
More genetic issues
Abnormal development
Ethical issues
Four steps to cloning
1. fragmentation - breaking apart a strand of
DNA
2. ligation - gluing together pieces of DNA in a
desired sequence
3. transformation - inserting the newly formed
pieces of DNA into cells
4. screening/selection - selecting out the cells
that were successfully transferred with the
new DNA
Stem cells
• 3 types:
– Totipotent-can become any type of cell
– Pluripotent-can be anything but a sex cell
– Multipotent-can be just a few other types
• Ex: bone marrow cells
• Adult stem cells cells are removed, and used to
grow more cells of specific tissue types
– Used to replace damaged tissue
• Embryonic stem cells-cells from embryos have
potential to become all different types of cells
Uses for stem cells
• To help aid in some cancers such as ones that
are tumor related
• Transplants
• Genetic engineering
• Organ failure
• Embryonic almost anything
Steps for creating stem cells
Selective breeding
• The method of artificially seelecting and
breeding only organisms with a desired trait to
produce the next generation.
• In other words, you select mates based on the
traits you want
– Ex: crops, domesticated animals
• Once the breeder has successfully produced
offspring with the desired set of
characteristics, inbreeding will occur
Hybridization
• Another form of selective breeding to choose
and breed organisms that show strong
expression for two different traits in order to
produce the offspring that express both traits.
• This often occurs between two different (but
similar) species. The offspring are often
healthier than the parents
• Ex: Mule, killer bees, Zonkey, Zorse, Liger,
Jaglion
• In nature polar bear-grizzly bear hybrid with
DNA confirmation
DNA fingerprinting or gene mapping
•Method of comparing different
strands of DNA with those of other
species or with other people
•Method used for formal pregnancy
test, crime investigations, and other
forensics
Gel electrophoresis
Gene Map