Biotechnology
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Recombinant DNA Technology
Gene Sequencing (Human Genome Project)
Cloning
Stem Cell Research
Gene Therapy
DNA Fingerprinting (and other Forensics applications)
DNA Cloning
Cloning is the production of identical copies of DNA
1. Stems or root send up new shoots that are clones of the parent plant.
2. Members of a bacterial colony on a petri dish are clones because they all came from division of the same
cell.
3. Human identical twins are clones; the original single embryo separate to become two individuals. (Artificial
Twinning)
4. Somatic Cell Nuclear Transfer (SCNT) – adult cells used to create an embryo
Gene cloning is production of many identical copies of the same gene.
1. If the inserted gene is replicated and expressed, we can recover the cloned gene or protein product.
2. Cloned genes have many research purposes: determining the base sequence between normal and mutated
genes, altering the phenotype, obtaining the protein coded by a specific gene, etc.
3. Humans can be treated with gene therapy: alteration of the phenotype in a beneficial way.
Recombinant DNA Technology
1. Recombinant DNA (rDNA) contains DNA from
two or more different sources.
2. To make rDNA, technician selects a vector.
3. A vector is a plasmid or a virus used to transfer
foreign genetic material into a cell.
4. A plasmid is a small accessory ring of DNA in
the cytoplasm of some bacteria.
5. Plasmids were discovered in research on
reproduction of intestinal bacteria Escherichia coli.
6. Introduction of foreign DNA into vector DNA to
produce rDNA requires two enzymes.
a. Restriction enzyme is a bacterial enzyme that
cuts DNA, it creates fragments of DNA with “sticky
ends”
b. DNA ligase joins fragments together
The Polymerase Chain Reaction
1. PCR can create millions of copies of a single gene or a specific piece of DNA in a test tube.
2. The polymerase chain reaction (PCR) uses the enzyme DNA polymerase to carry out multiple replications (a chain
reaction) of target DNA.
Analyzing DNA Segments
1. Mitochondria DNA sequences in modern living populations can decipher the evolutionary history of human
populations.
2. DNA fingerprinting is the technique of using DNA fragment lengths, resulting from restriction enzyme cleavage
and amplified by PCR, to identify particular individuals.
a. DNA is treated with restriction enzymes to cut it into different sized fragments.
b. During gel electrophoresis, fragments separate according to length, resulting in a pattern of bands.
c. DNA fingerprinting can identify deceased individuals or perpetrators of crimes
3. PCR amplification and DNA analysis is used to:
a. detect viral infections, genetic disorders, and cancer;
b. determine the nucleotide sequence of human genes: the Human Genome Project; and
c. associate samples with DNA of parents because it is inherited.
Biotechnology Products
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Genetically engineered organisms can produce biotechnology products.
Organisms that have had a foreign gene inserted into them are transgenic.
A. Transgenic Bacteria
1. Bacteria are grown in large vats where they can make products such as insulin and human growth hormone, and
vaccines
2. Transgenic bacteria have been produced to improve the health of plants and degrade substances, such as oil
3. Transgenic bacteria can produce chemical products, such as phenylalanine (artificial sweeteners)
B. Transgenic Plants
1. Foreign genes now give cotton, corn, and potato strains the ability to produce insect toxin s
2. Plants are being engineered to produce human proteins
including hormones, clotting factors, and antibodies
C.
Transgenic Animals
Animal use requires methods to insert genes into eggs of animals
(early in development). Using this technique, many types of
animal eggs have been injected with bovine growth hormone
(bGH) to produce larger fishes, cows, pigs, rabbits, and sheep.
“Gene pharming” is the use of transgenic farm animals to produce
pharmaceuticals; the product is obtainable from the milk of
females.
D. Cloning Transgenic Animals
1. The cloning of Dolly in 1997 showed that mammals could be
cloned.
2. Cloning of mammals involves injecting the nucleus of an adult
cell into an enucleated egg.
3. The cloned eggs begin development in vitro and are then
returned to host mothers until the clones are born.
Genomics
Genetics in the 21st century concerns genomics: the study of genomes of humans and other organisms.
A. Sequencing the Bases
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The Human Genome Project has produced a working draft of all the base pairs in all our
chromosomes.
The task took 13 years to learn the sequence of the three billion base pairs along the length of our
chromosomes.
Other organisms are being sequenced to compare genes and located genes responsible for
disorders.
The HapMap Project -- catalogs sequence differences, called haplotypes, in humans.
The Genetic Profile
1. DNA microarrays identify a person’s complete genotype; this is called the genetic profile.
2. DNA profiles can determine if a person has an increased risk for a particular disease
3. The genetic profile can be used to determine if a particular drug therapy is appropriate in a specific
clinical condition.
Proteomics
1. Proteomics is the study of the structure, function, and interaction of cellular proteins.
2. The information obtained from proteomic studies can be used in designing better drugs, and to
correlate drug treatment to the particular genome of the individual.
Bioinformatics
1. Bioinformatics is the application of computer technologies to the study of the genome.
2. Information obtained from computer analysis of the genome can show relationships between
genetic profiles and genetic disorders.
Gene Therapy
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Gene therapy involves procedures to give patients healthy genes to make up for a faulty gene.
Gene therapy also includes the use of genes to treat genetic disorders and various human illnesses.
There are ex vivo (outside body) and in vivo (inside body) methods of gene therapy.
Application of Biotechnology
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Describe the function of restriction endonucleases and explain 3 applications of their use in molecular biology.
Distinguish between sticky ends and blunt ends produced during a restriction enzyme digestion of DNA.
Sketch and label how gene cloning can be achieved using bacterial plasmids.
Describe the purpose of Genomic Libraries in biotechnology.
Sketch and label how Polymerase Chain Reaction works.
Answer questions 1-3 in your book on page 405.
Sketch and label how Gel Electrophoresis works.
Provide 3 examples of how gel electrophoresis is used in biotechnology.
Describe what RFLPs are and how they can be used to distinguish normal and abnormal cells. Provide one clear
example of their application.
10. Describe what SNPs are and how they can be used as genetic markers to identify genetic disorders.
11. Distinguish between totipotent and pluripotent stem cells and describe how they can be used in biotechnology.
12. Identify 3 applications of DNA technology in human medical research. Describe each application and provide the
advantages of applying such technologies.
13. Describe what genetic profile is and explain the application of STRs in forensic science.
14. Describe how genetically engineered organisms are being currently used in environmental cleaning and
agriculture practices.
15. Scientists have cloned sheep but have not yet cloned a human. The best explanation for this situation is that
A. There are many ethical problems involved in cloning humans
B. The technology to clone humans has not been explored
C. Human reproduction is very different from that of other mammals
D. Cloning humans would take too long
16. Which process is illustrated in the diagram below?
A.
B.
C.
D.
Selective breeding
Genetic engineering
Therapeutic cloning
Genetically modified crops
Use the diagram below to answer question 17 and 18.
17. One common use of this technology is the
A. Production of human embryos to aid women who are unable to have children
B. Change of single celled organisms to multicellular organisms
C. Production of missing body chemicals, like the hormone insulin
D. Introduction of a toxic substance to kill bacterial cells
18. Structure B represents which of the following molecules?
A. A ribosome
C. Transfer RNA
B. Recombinant DNA
D. An enzyme
19. How would genetically altering plants for pest resistance be economically beneficial?
A. Erosion of topsoil would no longer be a concern
B. Crops would be more easily protected from weeds
C. Crop-eating pests would no longer ruin crops
D. Abnormal plant growth would be eliminated
20. The gene for the production of human insulin is inserted into certain bacterial cells. The offspring of these
bacterial cells will most likely be able to
A. Destroy pathogens
B. Synthesize this hormone
C. Reproduce sexually
D. Form human tissue
21. What is the significance of the Human Genome Project?
A. The cause of cancer was discovered
B. The 3 billion bases in human DNA were discovered
C. The structure of DNA and how it is made was determined
D. All of the proteins made by human DNA were discovered
22. Which transplant method would prevent the rejection of an organ after a transplant?
A. Using organs cloned from the cells of the patient
B. Using organs produced by genetic engineering to get rid of all proteins in the donated organs
C. Using organs only from pigs or monkeys
D. Using an organ donated by a close relative
Use the image to answer questions 23and 24:
23. Which person’s DNA matches the blood stain?
A. Bob
C. John
B. Sue
D. Lisa
24. What process created the image above?
A. Human genome project
B. Gene mapping
C. Polymerase chain reaction
D. Gel electrophoresis