How to print this document: 1. Recombinant/ Cell Trans GMOs Cloning Stem Cells HGP Gel Electrophoresis

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1 How to print this document: 1. Recombinant/ Cell Trans GMOs Cloning Stem Cells HGP Gel Electrophoresis 41-43

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3 Cell Transformation A cell takes in DNA from outside the cell This external DNA becomes a component of the cell s DNA = Recombinant DNA Organisms that contain genes from other organisms are known as transgenic organisms. (Trans= change, genic= genes, because their genes have been changed).

4 Transformation Steps: 1. Locate desired DNA in donor organism 2. Foreign DNA is inserted into a bacterial plasmid 3. Bacteria takes in plasmid 4. Bacteria then replicates the foreign DNA 5. Produces product

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6 Importance of Transgenic Organisms Increase genetic variability Cheaply produce human proteins for use in medicine Human insulin Improve food supply Can produce crops that are resistant to weed-killing chemicals

7 Also called Recombinant DNA Technology: Recombinant DNA technology uses the natural process of transcription and translation to alter or change organisms. The DNA containing the desired gene is cut into pieces by humans. The fragment that contains the desired genetics is inserted into the genome of a microscopic biological agent like bacteria or a virus. The newly inserted DNA segment will now produce the desired protein. The biological agent contains the recombinant DNA. Once inserted into a human, it reproduces, inserting the desired DNA segment into other cells.

8 Example of Recombinant DNA Technology: Human insulin has been created using recombinant DNA technology. This was one of the biggest breakthroughs in recombinant DNA technology! Biosynthetic "human" insulin, was the first medicine made via recombinant DNA technology ever to be approved by the FDA. And it was all done with the help of E.coli bacteria!

9 In humans: Gene Therapy Using genes to treat or prevent diseases Insert genes into a patient s cell instead of a drug or surgery Replace mutated gene Inactivate a mutated gene E.g. Cystic Fibrosis

10 Why is Recombinant DNA (rdna) important? Recombinant DNA will only become more important in the 21st century as genetic diseases become more prevalent and agricultural area is reduced. Below are some of the areas where Recombinant DNA will have an impact.

11 Gene Therapy What is Gene Therapy? Gene therapy is inserting a normal gene in cells to replace a defective or missing gene in order to correct genetic disorders. How does it work? Gene therapy works by using viruses to deliver the correct gene to the cell. The virus carries the correct gene, and once it combines with the cell s DNA, all the new cells formed from cell division will have the correct version of the gene. What are examples of gene disorders that can be corrected by Gene Therapy? Cystic Fibrosis What is Cystic Fibrosis? Cystic Fibrosis (CF) is an inherited disease that causes the body to produce mucous that is very thick and sticky. The thick mucous leads to trouble breathing and infections. It is caused by one defective gene, which codes for a protein making the thicker mucous. Most sufferers die by age 30. How can CF be treated? CF can be treated using Gene Therapy. The defective gene can be replaced by a healthy gene, in order for the person to make the correct protein. This would lead to normal mucous consistency.

12 Gene Therapy Benefits of Gene Therapy: Helps cure diseases at the genetic level Concerns of Gene Therapy: The virus may not insert the correct gene properly, resulting in more complications and potentially the creation of serious disorders. The technology is expensive and may only be accessible to the rich, meaning the rich may get richer and the poor poorer It involves manipulating genetic makeup and altering nature. This is like playing God

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14 Genetically Modified Organisms (GMO s) Organisms whose genetic material has been artificially manipulated through genetic engineering

15 Genetically Modified Organisms (GMOs) A genetically modified organism (GMO) is an organism whose genetic material has been altered using genetic engineering techniques. The general principle and foundation of producing a GMO is to add new genetic material into an organism's genome to generate new traits. This is called genetic engineering and was made possible through a series of scientific advances including the discovery of DNA and the creation of the first recombinant bacteria in 1973, i.e., E.coli expressing a salmonella gene. Examples of GMOs: transgenic animals, such as mice, fish, various microbes, such as fungi and bacteria.

16 Genetically Modified Organisms (GMOs) The creation and use of GMOs has many reasons, chief among them are their use in research that addresses fundamental or applied questions in biology or medicine, for the production of pharmaceuticals and industrial enzymes, and for direct, and often controversial, applications aimed at improving human health (e.g., gene therapy) or agriculture (e.g., golden rice). The term "genetically modified organism" does not always imply, but can include, targeted insertions of genes from one into another species. These and other methods are useful and indispensable tools for biologists in many areas of research, including those that study the mechanisms of human and other diseases or fundamental biological processes in eukaryotic or prokaryotic cells.

17 Genetically Modified Organisms (GMOs) Transgenic animals Transgenic animals are used as experimental models to perform genetic tests with genes whose function is unknown or to generate animals that are susceptible to certain compounds or stresses for testing in biomedical research. Other applications include the production of human hormones, such as insulin. Frequently used in genetic research are transgenic fruit flies (Drosophila melanogaster) as genetic models to study the effects of genetic changes on development. Flies are often preferred over other animals for ease of culture, and also because the fly genome is somewhat simpler than that of vertebrates. Transgenic mice are often used to study cellular and tissue-specific responses to disease

18 Examples of GMO s: BT Corn Drought Resistant crops Medicine

19 Advantages of GMO s: Increase food supply: Freeze resistance Pest resistance Decrease food prices Research use: Medicine Drugs Gene Therapy

20 Disadvantages of GMO s: May interbreed with wild organisms and spread a gene that is not naturally occurring in the population Environmental impacts Chemical contamination Chemical traces in food Human Health No long-term data In U.S. labels aren t required

21 Genetically Modified Organisms Crops/ Plants Transgenic plants have been developed for various purposes, including: 1) resistance to pests, herbicides or harsh environmental conditions, 2) improved product shelf life, and 3) increased nutritional value. Whenever GM plants are grown on open fields without containment there are risks that the modification will escape into the general environment. Most countries require biosafety studies prior to the approval of a new GM plant release, usually followed by a monitoring program to detect environmental impacts. The use of GMOs has sparked significant controversy in many areas. Some groups or individuals see the generation and use of GMO as intolerable meddling with biological states or processes that have naturally evolved over long periods of time, while others are concerned about the limitations of modern science to fully comprehend all of the potential negative ramifications of genetic manipulation. While some groups advocate the complete prohibition of GMOs, others call for mandatory labeling of genetically modified food or other products. Other controversies include the possibility of unforeseen local and global effects as a result of transgenic organisms proliferating.

22 Genetically Modified Organisms Crops/ Plants Important example: Golden rice is a variety of rice (Oryza sativa) produced through genetic engineering to biosynthesize beta-carotene, a precursor of vitamin A in the edible parts of rice. The research that led to golden rice was conducted with the goal of helping children who suffer from Vitamin A Deficiency. At the beginning of the 21st century, 124 million people, in 118 countries in Africa and South East Asia, were estimated to be affected by Vitamin A deficiency. It is responsible for 1 2 million deaths, 500,000 cases of irreversible blindness and millions of cases of xerophthalmia annually. Children and pregnant women are at highest risk. Unfortunately, the rice is still not available for human consumption because of the very strong oppositions.

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25 Cloning Producing genetically identical individuals Cloned a sheep named Dolly Dolly and her DNA donor are genetically identical Ethical concerns for cloning humans

26 Cloning Cloning is another example of BIOTECHNOLOGY. Genetically identical individuals are created from a DONOR cell. In a basic sense, scientists are able to use a single cell from an adult to grow an entirely new individual that is completely IDENTICAL without the help of another parent. Although the process is relatively straightforward in simple organisms such as bacteria, this is not the case for multicellular organisms such as SHEEP. DOLLY is a sheep and was the first animal to be cloned successfully. Dolly was the 277 th attempt in cloning a mammal and her death spared a huge array of new research questions. To clone an animal, (1) an egg is taken from an adult female and the NUCLEUS of a female egg is removed. (2) The remaining egg cell is then injected with the nucleus of a cell taken from another adult. (3) When they fuse, they produce a single cell that begins to DIVIDE. (4) Once the single cell has become an embryo, it is then placed inside of the UTERUS a FOSTER mother. (5) Eventually, it develops into an offspring that is genetically identical to the original animal that donated the NUCLEUS. Researchers hope that by cloning animals, they can help endangered species populations recover or produce animals that can genetically PRODUCE substances with significant commercial or medical value. Another possible benefit would be creating tissues for transplantation that would not be rejected by their host and using genetically altered cells to CURE people with Alzheimer s or Parkinson s. Cloning creates serious ethical concurs, however. One of these concerns is that someone will both try and succeed at cloning a HUMAN. In the United States, federal research funds are not given to scientists who research human cloning, but the research is not FORBIDDEN.

27 Cloning Cloning is the processes used to create exact copies of DNA fragments (molecular cloning), cells (cell cloning), or organisms. Dolly, a sheep, was the first mammal to have been successfully cloned from an adult cell, though the first actual thing to be cloned, was a tadpole in Dolly was publicly significant because the effort showed that the genetic material from a specific adult cell, programmed to express only a distinct subset of its genes, could be reprogrammed to grow an entire new organism. Many animals have been cloned, including horses, cats, cows, rhesus monkey, tadpoles, sheep, mice, carp (fish), and a mule! Two types of human cloning: Therapeutic cloning involves cloning cells from an adult for use in medicine and is an active area of research Reproductive cloning would involve making cloned human beings. Such reproductive cloning has not been performed and is illegal in many countries.

28 Cloning Ethical issues of cloning There are MANY sides to the issue of cloning! Some people think all cloning is wrong, some think only reproductive cloning is wrong, and others believe that cloning (including human cloning!) is a technology that should continue to be researched. Animals are cloned without these ethical issues. According to the US Food and Drug Administration, food coming from cloned animals is safe to eat. In addition the FDA stated that cloned food does not require special labeling. Both meat and milk from cloned animals such as swine, goats and cattle have no differences from the conventionally bred animals. Cloning extinct and endangered species Just think of the movie Jurassic Park! In real life, some endangered species have been successfully cloned! This would allow scientists to preserve certain organisms if they are in danger!

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30 Stem Cell Research Primary Goal: Grow organs for transplant surgery

31 Stem Cells The human body produces billions of new cells every day. Most of these cells have very specific jobs. Early in development, they become specialized as different types of cells, such as blood, muscle, or brain. Some cells, however, are not specialized. Instead they can develop into a wide variety of cells. These are referred to as stem cells. Researchers hope that stem cells hold the key to replacing cells that have been damaged from injury or disease or can no longer regenerate. What is a Stem Cell? Stem cells are special cells with unique growth characteristics. They can make identical copies of themselves, as well as grow into more specialized cells. There are two types of Stem Cells: Embryonic Stem Cells and Adult Stem Cells. Embryonic Stem Cells are preferred by scientists because they are the only type that can be grown in large numbers in a laboratory. They also retain the ability to grow into any cell in the body, unlike Adult Stem Cells. Adult Stem cells are harder to grow in the laboratory and are more limited in the types of cells they can make.

32 Ethical Issues: Stem Cells In order to get Embryonic Stem Cells, an embryo is destroyed. This has caused people to question the morality and ethics of stem cell research. The use of stem cells are controversial for a number of reasons, but also have the potential for curing diseases. PROS: 1. Help fin cures and treatments for many diseases like Parkinson s, Alzheimer s, spinal cord injuries and cancer. 2. Can be used to generate new organs or tissue that is an identical match to the donor. 3. Better and more natural alternative to current drug and radiation treatments. 4. SAVES LIVES CONS: 1. It destroys a human embryo, which means life is destroyed if you think life starts at conception. 2. We are messing too much with life and playing God. 3. Stems cells can cause cancer if they are not programmed correctly.

33 Stem cells are cells found in most, if not all, multi-cellular organisms. They are special because they can renew themselves through dividing and differentiating (specializing) into a diverse range of specialized cell types. Embryonic stem cell lines (ES cell lines) are cultures of cells derived from embryos. ES cells are pluripotent which means they can become ANY cell in the body! Adult stem cells are any cell found in a developed organism that has two properties: the ability to divide and create another cell like itself and also divide and create a cell more differentiated than itself. They can be found in children, as well as adults. You have them in your body! Stem Cells

34 Stem Cells In Medicine Adult stem cell treatments have been successfully used for many years to treat leukemia and related bone/blood cancers through bone marrow transplants. The use of adult stem cells in research and therapy is not as controversial as embryonic stem cells, because the production of adult stem cells does not require the destruction of an embryo. Medical researchers believe that stem cell therapy has the potential to dramatically change the treatment of human disease. A number of adult stem cell therapies already exist, particularly bone marrow transplants that are used to treat leukemia. Some day, stem cell research could be used to treat a wider variety of diseases including: cancer Parkinson's disease spinal cord injuries muscle damage However, there still exists a great deal of social and scientific uncertainty surrounding stem cell research, which could possibly be overcome through public debate and future research, and further education of the public.

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36 Human Genome Project: ongoing effort to analyze the human DNA sequence completed copy of human DNA sequence Goal: determine genetic make-up of humans Advantages: helps with gene therapy and treatment of genetic disorders

37 Human Genome Project What is the Human Genome Project (HGP)? In 1990, scientists around the world formally began the Human Genome Project. One of the main goals of the project was to identify the approximately 30,000-40,000 genes in human DNA. A second goal was to determine the sequences of the 3 billion chemical base pairs (nitrogen bases) that make up human DNA. They aimed to make a map of every gene in the human body. The tremendous undertaking was expected to take 15 years, but improvements in technology enabled scientists to achieve their goals in less time. The project was completed in DID YOU KNOW? A genome is a complete set of an organisms DNA. There are about 3 billion base pairs in the human genome. Hundreds to thousands of genes are located on each of the 46 chromosomes. Each genes makes an average of three proteins. What are some of the Ethical Concerns? In addition to a tremendous amount of work and a hefty price tag, the Human Genome Project also came with its own controversy. Although researchers hope to use the information to detect and treat abnormalities that lead to disease, others worry that humans are exerting too much control over nature. Opponents are afraid that the information could lead to a future where parents genetically select everything from eye color to intelligence for their offspring, the super humans!

38 Human Genome Project Critical Policy and Ethical Issues From its inception, the Human Genome Project dedicated funds to identify and address the ethical, legal, and social issues surrounding the availability of new genetic data and capabilities. Examples of such issues follow.* Privacy and confidentiality of genetic information. Who owns and controls genetic information? Is genetic privacy different from medical privacy? Fairness in the use of genetic information by insurers, employers, courts, schools, adoption agencies, and the military, among others. Who should have access to personal genetic information, and how will it be used? Psychological impact, stigmatization, and discrimination due to an individual's genetic makeup. How does personal genetic information affect self-identity and society's perceptions? Reproductive issues including adequate and informed consent and the use of genetic information in reproductive decision making. Do healthcare personnel properly counsel parents about risks and limitations? What are the larger societal issues raised by new reproductive technologies? Clinical issues including the education of doctors and other health-service providers, people identified with genetic conditions, and the general public; and the implementation of standards and quality-control measures. How should health professionals be prepared for the new genetics? How can the public be educated to make informed choices? How will genetic tests be evaluated and regulated for accuracy, reliability, and usefulness? (Currently, there is little regulation.) How does society balance current scientific limitations and social risk with long-term benefits? Fairness in access to advanced genomic technologies. Who will benefit? Will there be major worldwide inequities?

39 Human Genome Project The Human Genome Project was a 13-year project coordinated by the U.S. Department of Energy and the National Institute of Health. The goal was to characterize all human genetic material by determining the complete sequence of DNA in the human genome. The Human Genome Project's ultimate goal is to discover and map all of the approximately 35,000 human genes and make them accessible for further biological study. It completed its initial mission in The initial purpose or goals were to: identify all the approximately 20,000-25,000 genes in human DNA, determine the sequences of the 3 billion chemical base pairs that make up human DNA, store this information in databases, improve tools for data analysis, transfer related technologies to the private sector, and address the ethical, legal, and social issues (ELSI) that may arise from the project. Some of the application areas where specific goals (additional purposes) have been defined are as follows: Molecular Medicine Energy and Environmental Applications Risk Assessment Bioarchaeology, Anthropology, Evolution DNA Forensics Agriculture, Breeding We now understand that there are approximately 35,000 genes in each human DNA molecule! We now appreciate that the DNA structure is one of the greatest scientific discoveries of all time, only first discovered at its base level in 1953 by James Watson and Francis Crick.

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41 DNA Fingerprinting Using Genetics to Fight Crime Since the early 1900s, detectives have used fingerprints to identify criminals. Every person has a special and unique fingerprint, so someone s fingerprints left at the scene of a crime can be used as evidence to identify them. More recently, scientists have teamed up with detectives to find a much more powerful tool for finding evidence in crimes: DNA fingerprinting. Just like everyone has a unique fingerprint, every person has unique DNA. A drop of dried blood or a single hair contains a DNA fingerprint that belongs only to the person it came from. To find a DNA fingerprint, scientists perform an experiment called electrophoresis (eee-lek-tro-for-ee-sis). Scientists take hair, blood, semen, or any other material left at a crime scene and isolate the DNA inside of it. Then, they place the DNA in a special gel and run electricity through the gel. The gel separates the DNA into separate groups, called fragments. Since everyone has different DNA, each person s DNA will have a different pattern of fragments. Scientists take the DNA left at the scene of the crime, and place it in gel along with DNA from the victim and any suspects. If the pattern of the DNA from blood or hair found at the crime scene matches the pattern of the DNA from a suspect, they know that blood or hair belongs to the suspect.

42 DNA Fingerprinting That first case led to the conviction of Tommie Lee Andrews for rape. A woman was raped, and semen was collected from her body within hours of the attack. Then, during the trial, investigators took a blood test from Andrews, the suspect. DNA from the semen, Andrews blood, and the victim s blood were placed in a gel and separated. The result is at right. What do you see? Do the DNA fragments from Andrews (labeled as suspect ) match the DNA of semen (labeled rapist s semen ) left by the rapist? If so, then the semen belonged to Andrews, and he was the criminal. A scientist who worked on the Andrews case to use DNA fingerprinting said that leaving DNA fingerprints is like leaving your name, address, and social security number at the scene of the crime. It s that precise. The information in our DNA is extremely powerful. When electrophoresis is used for DNA fingerprinting in a court case, it must be done very carefully. There is DNA everywhere in skin cells, in bacteria that live in the air or on lab equipment. So, it is very easy for DNA from somewhere else to contaminate the DNA from the crime scene and ruin the DNA fingerprint. Scientists must wear gloves and goggles while handling DNA and equipment, and work in a sterile (clean) environment. All equipment and counters must be wiped down and disinfected.

43 DNA Fingerprinting Advantages 1. It helps people know more about their family background. 2. It helps solve crimes. 3. It can help determine and even prevent illnesses. Disadvantages 1. It can violate people s privacy. 2. It can point the finger at the wrong person in a criminal investigation. 3. It s complex and there can be mistakes. Final Thoughts DNA fingerprinting has several advantages and can help both the authorities and ordinary people. However, it does have its own drawbacks, so it s up to the experts to make sure that the DNA fingerprinting process is used properly and wisely.