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Biotechnology in a Political World. Biotechnology in a Political World. I. Significance of “Biotechnology in a Political World”. A. Biotechnology is regulated by the US Government
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Biotechnology in a Political World Biotechnology in a Political World
I. Significance of “Biotechnology in a Political World” A. Biotechnology is regulated by the US Government i. The regulation of biotechnology involves: Congress, United States Department of Agriculture (USDA), Food and Drug Administration (FDA), Environmental Protection Agency (EPA), National Institute of Health (NIH), Department of Energy (DOE), State governments, and a host of other committees and groups. ii. Many public and government officials are involved in biotechnology’s regulation including: officials ranging from the president and cabinet level members to state congressmen and voters.
Significance Con’t B. Biotechnology’s impacts will be significant and far reaching i. Biotechnology can and will fundamentally change: the way many common day products are produced such as food, medicine, and clothing. ii. With the advent of advanced cloning techniques and “human engineering” biotechnology has the possibility of altering our perception of life and time.
Significance Con’t iii. Because of the large impact that biotechnology will have on the future, our group felt that it was important that political science students at JMU be exposed to some important issues and concepts associated with biotechnology. iv. As a result of this brief exposure, we hope to instill in each of you a sense of sensitivity, enthusiasm, and respect for biotechnology issues.
Objectives of Day #1 of Class A. Students should gain a better understanding of the pervasive nature of biotechnology. B. Students should become familiar with DNA and its structure and function. C. Students should be able to give some examples of cloning and how it is currently used and regulated in the US.
II. Class Exercise: What’s in the Bag? courtesy of Photo Disk, Inc. courtesy of Expert Software, Inc. Courtesy ofExpert Software, Inc.
Class Exercise Con’t A. List of bag items and whether or not they are involved in biotechnology. B. As it has been illustrated, biotechnology is involved in a wide range of processes: ranging from stone washing blue jeans to the creation of medicine. C. While this is true, our discussion is going to focus on three of the most provocative and significant advancements being made in current biotechnology research. These three areas will be: cloning, genetic screening, and genetic fingerprinting. D. Before this investigation can begin, however, some basic cellular biology concepts must be reviewed.
III. Background Information on Cellular Biology A. DNA (or deoxyribonucleic acid) is the blueprint of life for all living things on Earth from fungus to monkeys to humans.For each organism, the components of these slender threads encode: all the information necessary for building and maintaining life. i. If unwound and tied together, the strands of DNA that code for a human being would stretch more than 5 feet but would be only 50 trillionths of an inch wide. ii. Understanding how DNA performs this magnificent feat requires some knowledge of its structure and organization.
What is DNA... iii. DNA’s structure: DNA is a double-stranded molecule held together by weak bonds between base pairs of nucleotides. • a. Nucleotides are molecules composed of one sugar, one • phosphate and a nitrogenous base. • b. The four nucleotides in DNA contain the bases: adenine • (A), guanine (G), cytosine (C), and thymine (T).
courtesy of Denise Casey Human Genome Management Information System
What is DNA Con’t... c. In nature, base pairs form only between A and T and between G and C; thus the base sequence of each single strand can be deduced from that of its partner. d. The particular order of the bases arranged along the sugar- phosphate backbone is called the DNA sequence; the sequence specifies the exact genetic instructions required to create a particular organism with its own unique traits.
From DNA to Genes to Genomes a. An organism’s entire collection of DNA is referred to as its genome. The human genome contains approximately three billion base pairs. b. While an organism’s genome may seem like one long chain of information, it is in actuality several separate chains organized into discrete areas. Each of these areas holds the code for specific duties. The most basic of these divisions is referred to as a gene. c. Gene: The fundamental physical and functional unit of heredity. A gene is an ordered sequence of nucleotides located in a particular position on the DNA chain that encodes for one specific functional product (i.e., a protein or RNA molecule).
From DNA to Genes to Genomes Con’t d. Human genes vary widely in their size, and many are comprised of thousands of base pairs. e. While the human genome contains an estimated 65,000 – 80,000 not all of these are expressed. In fact, it is believed that only about 10% of human genes are expressed. f. Gene expression: The process by which a gene’s coded information is converted into the structures present and operating in the cell. This process is very complex, but an overview will be provided in section III. v.
From DNA to Genes to Genomes Con’t g. All human genes are linearly organized into 24 distinct, physically separate units: called chromosomes. h. The nucleus of most human cells contains 2 sets of chromosomes, 1 set given by each parent. Each set has 22 single chromosomes and an X or Y sex chromosome. A female has two X chromosomes; a male has one X and one Y chromosome. i. A few types of major chromosomal abnormalities, including missing or extra copies of a chromosome or gross breaks and rejoinings, can be detected by microscopic examination; Down’s syndrome, in which an individual's cells: contain a third copy of chromosome 21.
courtesy of Denise Casey Human Genome Management Information System
From DNA to Genes to Genomes Con’t ***Note: Within a normal cell the individual chromosomes are not distinguishable. However, during cell division they can be separated out as illustrated in this figure. j. Most changes in DNA, however, are too subtle to be detected by microscopic analysis and require molecular analysis. These subtle DNA abnormalities (mutations) are responsible for many inherited diseases such as: cystic fibrosis and sickle cell anemia or may predispose an individual to cancer, major psychiatric illnesses, and other complex diseases.
courtesy of Denise Casey Human Genome Management Information System
The Code for Protein Production a. While DNA acts as the blue print for life, it is the proteins that are produced that carry out all the complex functions of life. b. Proteins are large, complex molecules made up of long chains of sub-units called: amino acids. c. Twenty different kinds of amino acids combine to form all of the different types of proteins in the human body. d. Within the gene, each specific sequence of three DNA bases (codons) directs the cells protein-synthesizing machinery to add specific amino acids.
The Code for Protein Production Con’t e. For example, the base sequence ATG codes for the amino acid methionine. Since 3 bases code for 1 amino acid, the protein coded by an average sized gene (3000 bp) will contain 1000 amino acids. The genetic code is thus a series of codons that specify which amino acids are required to make up specific proteins.
courtesy of Denise Casey Human Genome Management Information System
DNA and its Relation to the Cell i. The Nucleus a. All cells DNA is contained: within the cell nucleus. b. How then is information transported from inside the cell nucleus to the rest of cell for protein production……..? The answer is via RNA (or ribonucleic acid) Courtesy of Catherine Baker Department of Energy
RNA and its Relation to the Cell c. A great amount of information is known about RNA, however, for this discussion, the important thing to remember is that RNA is used to transport information: from the cell nucleus to other parts of the cell. b. There are several reasons why DNA remains in nucleus: 1. more stable environment 2. less likelihood of mutation 3. centralized location
Cytoplasm and its Relation to the Cell ii. The Cytoplasm a. All of the cells protein production occurs in the area outside of the nucleus known as the cytoplasm. b. The nucleus is the cell’s brains, while the cytoplasm is the cell’s body.
Differentiation and Stem Cells i. Differentiation a. All of the cells in the human body (except sperm and egg cells) contain the complete set of DNA for that individual. b. Why is it then that heart cells function differently from nerve cells, which function differently from liver cells, even though they all have the same DNA? This is due to cell differentiation. c. Cell differentiation: The process by which cells mature so that they can perform separate functions. This is a result of different types of cells expressing different types of proteins.
Differentiation and Stem Cells Con’t ii. Stem Cells a. Stem cells are cells that act as a continuous source of a differentiated cell type. An example of these types of cells are those that exist in bone marrow and produce red blood cells throughout a persons life. b. One major area of research in biotechnology involves scientists trying to isolate and understand stem cells. If this can be done, they could potentially serve as a reservoir for unlimited amounts of cells. This reservoir could then be used in many different including: the treatment of burn victims, hemophilia, and defective organs to name just a few. c. Late in 1998, two independent research laboratories reported the isolation of human embryonic stem cells.
Germline vs. Somatic cells i. Basic Biological Differences a. Germline cells are cells that contain only half of the DNA necessary in order to create life. These include both sperm and egg cells. These cells are involved in sexual reproduction, and the mixing of there DNA results in the creation of a unique individual. b. Somatic cells are all other cells in the body, and contain the entire DNA of an individual. Figure 3.5 courtesy of Life Art, Inc. http://ehrweb.aaas.org/ehr
Germline vs. Somatic cells con’t ii. Ethical Differences in Their Manipulation a. Biotechnology is involved in manipulating the DNA of both germline and somatic cells. This manipulation includes the insertion, deletion, repair, and/or maintenance of genes both native and foreign to an organism’s DNA. There is; however, a very distinct ethical difference in the effects of changing a somatic cell vs. a germline cell. b. In changing the DNA of a somatic cell, only that cell, and the other cells that it might divide into will be changed. The change would only last for as long as the cell, and any cells it divided into, survived. The same is not true if the DNA of a germline cell is changed.
Germline vs. Somatic cells con’t c. In changing the DNA of a germline cell, the entire genetic code of any offspring brought into existence with this cell is changed. Additionally, if that offspring reproduces, its progeny will also be subject to the changes that we made in the DNA two generations earlier. d. Therefore, any genetic change to a somatic cell is temporary, while any change to a germline cell has the potential to genetically alter thousands of generations of offspring. e. Currently, germline research is limited to animals, but the application of germline manipulation technology to humans raises many ethical questions.
Questions?????????? Is it ethical to change the DNA of offspring that have no choice in accepting this change? What unknown risk apply to such manipulation, and can they be quantified? Do we understand genetics well enough to begin altering the very DNA that makes us human beings? Would it be ethical to change the DNA of a germline cell if it would prevent a child, and that child’s child, from suffering from some disease given the fact that other risks can not be quantified?
Questions?????????? Would it be ethical to change the DNA of a germline cell if it would change superficial characteristics of a child, and that child’s child, such as eye color, weight, or height? The answers to these questions are still undecided, and the technology allowing for such changes is rapidly approaching.
Biotechnology in a Political World Cloning: History, Techniques, and Legislation
Background • The word “clone” derived from the Greek “klon” meaning twig or slip • The original practice of cloning involves cutting a young branch from a plant or tree and planting it separate from the original plant. • When it grows, it will be an exact genetic copy of the original plant.
Background • In a more modern sense, cloning is the creation of genetically identical copies of molecules, cells, plants, and animals without the intervention of the sexual process.
Cloning History • Laboratory cloning experimentation dates back to 1894 at the University of Chicago • German born American physiologist Jacques Leob (1859 – 1924) was able to clone a cell for the first time.
History • In 1938 Hans Spemann extended Leob’s work to vertebrate embryos • Spemann was able to clone a salamander embryo
History • 1994: Robert J. Stillman and his team at the George Washington Medical Center publicly announced the first human embryo cloning • 1996: Dolly • late 1998: a Korean researcher reported the growth of a cloned human embryo
Nuclear Transfer and Dolly • July, 1996: Dr. Ian Wilmut of the Roslin Institute cloned an adult sheep. • The resulting lamb was the first successful mammalian clone.
Figure 2.2 Courtesy of: Joe Lertola for TIME Online Nuclear Transfer
Why Experiment? • Increased agricultural yields • plants that are pest resistant, cold/heat resistant • animals that are leaner and that produce more milk, etc.
Why Experiment? • Biodegradable plastics • Transgenic plants and bacteria can be made that produce these plastics • Bio-therapeutic agents • NEUTRACEUTICALS: enhancing milk using gene targeting and nuclear transfer to better suit special consumers such as infants or people who are lactose intolerant
Why Experiment? • Organs (human or other) transplantable into humans produced in animals such as pigs • Pregnancy and cell differentiation: • research could produce a greater understanding of the causes of miscarriages and could lead to treatment for spontaneous abortion
Why Experiment? • Researchers are learning about cell differentiation from human embryo cloning research: • if we learn how a cell (stem cell) becomes a different type of cell: then an isolated stem cell could be used to grow anything from skin, to heart muscle, to entire organs.
Why Experiment? • Human embryo cloning research may also lead to an understanding of the mechanisms by which a morula (a mass of cells that has developed from a blastula) attaches itself to the wall of the uterus: • This understanding could generate effective new contraceptives that would exhibit very few side effects.
Why Experiment? • Cancer Research: Patients undergoing chemotherapy • made real by cloning is the prospect of taking the nucleus from a marrow cell, putting it into another cell such as an enucleated egg, and producing marrow in culture, free of cancer and without fear of rejection
Why Experiment? • The creation of perfect experimental controls: • “Animals could be created to more accurately model human diseases and reactions to human therapeutic products” (Dr. Harold Varmus, Director of the NIH, in his prepared statement before Congress, 97).
Why Experiment? • Currently, testing is done on animals that are similar, but do have the exact same DNA as one another. This complicates testing and leads to reduced accuracy of experimental test results..
Why Experiment? • Cloning will increase the accuracy of testing for efficacy, potency, and unexpected adverse risk in experimental drugs and therapies. • This will in turn lead to safer and more effective treatment of human disease
Legislative History • Until recently, cloning has been a technique widely used, without controversy, in research labs around the world. This attitude was radically altered with the announcement of the world’s first cloned mammal, Dolly. • Aside from opening doors to new research, the cloning of Dolly thrust the issue of a possible attempt to clone a human into public debate.
Legislative History • Following the Roslin Institute’s announcement and Richard Seed’s thoughts, President Clinton signed an Executive Order to all federal agencies “that no federal funds shall be allocated for cloning of human beings” (Human Cloning Research Prohibition Act, 1997).
Legislative History • The President also called for the creation of the National Bioethics Advisory Committee (NBAC) • Science Committee examined the legal and ethical issues associated with the use cloning during a series of three hearings over five months: