I. OVERVIEW OF GENETIC ENGINEERING:
Biotechnology refers to technology used to ___________________DNA.
The procedures are often referred to as______________________________.
_________is the genetic material of all living organisms.
o All organisms use the ___________genetic code (A, T, C, G).
__________________________: organisms that contain functional recombinant DNA
___________________________refers to the DNA from the two DIFFERENT organisms.
o Can be used for creating transgenic organisms, gene therapy, cloning and gene
A. 3 Steps to Creating Recombinant DNA:
DNA is cut into small pieces using _______________________(RE).
o Restriction enzymes were discovered in__________________.
Bacteria use them as a defense mechanism to cut up the __________of
viruses or other bacteria
Hundreds of different ______________________have been isolated
Each restriction enzyme or RE cuts DNA at a SPECIFIC
For example, EcoRI always cuts DNA at GAATTC as indicated below
The sequence GAATTC appear three time in the below strand of DNA, so it is cut
into four pieces.
Fragments of DNA that has been cut with restriction enzymes have unpaired nucleotides
at the ends called___________________. Sticky ends have complimentary bases, so
______________: carries foreign DNA into host cell
o A vector must be _________________________________________inside a
o Two types of vectors:
1. __________________________: pipette or ______________
2. __________________________: plasmid or ___________
o A __________________is small ring of DNA in a bacterium.
_____________________& __________________are the most commonly used vectors
3. _______________________________________________________. When the host’s
cells reproduce, the desired protein or enzyme is also reproduced.
Diagram: Showing Recombinant DNA Technology.
II. GENETIC ENGINEERING: What Can We Do With
1. _______________________: A "normal" gene is inserted into the genome to replace an
"abnormal," disease-causing gene.
How does it work?
o A carrier molecule called a _____________must be used to deliver the
therapeutic gene to the patient's target cells.
o The most common vector is a ___________that has been genetically altered to
carry normal human DNA.
o Ex: To reverse disease caused by genetic damage, researchers isolate normal
DNA and package it into a vector, a molecular delivery truck usually made from
a disabled virus. Doctors then infect a target cell —usually from a tissue
affected by the illness, such as liver or lung cells—with the vector. The vector
unloads its DNA cargo, which then begins producing the missing protein and
restores the cell to normal.
The Food and Drug Administration (FDA) has __________yet approved any human
gene therapy product for__________. Current gene therapy is experimental and has
not proven very successful in clinical trials.
A. What factors have kept gene therapy from becoming an
effective treatment for genetic disease?
_____________________________________- DNA introduced into target
cells must remain functional and the cells containing the therapeutic DNA must be
long-lived and stable. Patients will have to undergo multiple rounds of gene therapy.
________________________________- human’s immune systems could
attach the therapeutic DNA and destroy it.
_____________________________________- viruses can present a variety of
potential problems to the patient --toxicity, immune and inflammatory responses, and
gene control and targeting issues.
___________________________________- Disorders that are caused by the
combined effect of many genes are very difficult to treat effectively.
2. ________________________: Rejoining cut fragments of DNA
Done chemically via __________________________(RE) that cut the DNA.
Each RE cuts a specific base pair, then scientists can add any genetic sequences they
wish into the DNA.
_________________ is used to produce ________________for diabetics:
o In the past, insulin was only obtainable from the pancreas of cadavers (and it
required 50 cadavers to yield one dose!).
o The insulin-producing genes from human DNA are spliced into plasmid DNA;
the plasmids are then allowed to infect________________, and, as the
bacteria multiply, large amounts of harvestable insulin are produced.
3. ____________________________: Creating genetically IDENTICAL copies
3 types of cloning technologies: recombinant DNA technology or DNA cloning,
reproductive cloning, and therapeutic cloning.
_____________________________________or __________________= the transfer
of a DNA fragment of interest from one organism to a self-replicating genetic element
such as a bacterial plasmid. The DNA of interest can then be multiplied in a foreign
___________________________________= generates an animal that has the same
nuclear DNA as another currently or previously existing animal.
Ex:__________: scientists transfer genetic material from the nucleus of a
donor adult cell to an egg whose nucleus, and thus its genetic material, has
been removed. The reconstructed egg containing the DNA from a donor cell
must be treated with chemicals or electric current in order to stimulate cell
division. Once the ________________ reaches a suitable stage, it is
transferred to the uterus of a female host where it continues to develop until
Celebrity Sheep Has Died at Age 6
Dolly, the first mammal to be cloned from adult DNA, was put down by lethal
injection Feb. 14, 2003. Prior to her death, Dolly had been suffering from lung
cancer and crippling arthritis. Although most Finn Dorset sheep live to be 11 to
12 years of age, postmortem examination of Dolly seemed to indicate that,
other than her cancer and arthritis, she appeared to be quite normal. The
unnamed sheep from which Dolly was cloned had died several years prior to her
creation. Dolly was a mother to six lambs, bred the old-fashioned way.
Image credit: Roslin Institute Image Library, http://www.roslin.ac.uk/imagelibrary/
_________________________________= also called "embryo cloning," is the
production of human embryos for use in research.
The goal of this process is to harvest stem cells that can be used to study
human development and to treat disease.
_______________________can be used to generate virtually any type of
specialized cell in the human body.
Stem cells are extracted from the egg after it has divided for 5 days.
The extraction process destroys the embryo, which raises a
Many researchers hope that one day stem cells can be used to serve as
replacement cells to treat heart disease, Alzheimer's, cancer, and other
4. ___________________________________: Genetically modified organisms are organisms
with artificially altered DNA. They can be created by:
________________________________: Organisms that are altered in this way are
known as transgenic organisms.
____________________________________________: (Gene therapy)
_____________________________________________: (so they don't produce their
o Ex: deactivating the gene responsible for the ripening of tomatoes. This new
gene can then be inserted into tomato DNA to give them a longer shelf life.
III. APPLICATIONS OF GENETIC ENGINEERING:
Incorporating bacterial genes for resistance to _________________, so a crop plant is
not killed by weed killer (herbicide).
• Incorporating bacterial genes, which produce their own _____________________into corn
plants. Herbivorous insects are thus prevented from eating such plants.
• Strawberry plants ________________to frost
• Bovine growth hormone – increases milk production in cow by 10%
• Goats - produce milk containing high levels of a human protein that dissolves blood clots
• B.T. cotton – Bacillus thuringiensis bacteria make a toxin against insects –
• ___________________zebra fish- inserted the protein for glowing from a jelly fish.
• Bacteria ___________________oil in oil spills- Some bacteria thrive on toxic waste. The
genes allowing breakdown of the toxic substance can be added to other more numerous
bacteria and then applied to toxic spills for cleanup (bioremediation).
• Bacteria ____________________minerals from ores
• _______________of Human Growth hormone, Human insulin, Interferon (treats cancer)
• Recombinant DNA techniques are used in __________________________
• Gene therapy can be used to help cure a genetic disease by replacing the defective one.
IV. SAFETY AND ETHICAL ISSUES:
____________________________________may be accidentally produced
Organisms that are intended to be released in the environment may be engineered with
genes that will eventually kill them.
There is ______________________on the use of genetic screening and information
produced by screening
The _________________________is increasing the ability to diagnose genetic diseases
prenatally, adding new complexity to the abortion controversy.
Ethical questions have been raised over whether we should _______________________
Genetic screening and gene therapy are __________________________and may be
unavailable to the middle class and low socioeconomic citizens.
______________________________could be created using biotechnology.