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Findings Magazine NIGMS Science Education Publications CD­ROM Containing NIGMS Science Education Materials Posters We would like your comments on The New Genetics. Please give us your feedback by filling out this postage­paid card. Browse and order free NIGMS educational publications at http://publications.nigms.nih.gov/order 1. How do you use this publication? Send me free poster(s) on: ❑ Living Laboratories 2. What do you like best about this publication? ❑ Chemistry ❑ Find Out (what it’s like to be a scientist) 3. How could we improve this publication? ❑ Send me a free CD­ROM containing all NIGMS science education materials for high school and early college students. 4. Do you have other suggestions or comments? Send me a free copy of the NIGMS science education The New Genetics booklet(s) on: ❑ cell biology Name ❑ chemistry and biochemistry School/Organization* ❑ computers and biology Grade Level* ❑ genetics ❑ pharmacology Address ❑ structural biology/proteins NIH Publication No. 10­662 ❑ Send me a copy of Findings, a free magazine with Revised April 2010 City profiles of scientists and more. http://www.nigms.nih.gov State ZIP Code ❑ Add my name to the mailing list for free future issues of Findings. U.S. DEPARTMENT OF E­mail (optional) Printed on XX% recycled paper. HEALTH AND HUMAN SERVICES ❑ single copy National Institutes of Health Read, Share, Recycle. National Institute of General Medical Sciences Phone (optional) ❑ class set ____ copies (limit 30) *required for multiple­copy orders ATTENTIONREADERS Discrimination Prohibited Under provisions of applicable public laws enacted by Congress since 1964, no person in the United States shall, on the grounds of race, color, national origin, handicap, or age, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any program or activity (or, on the basis of sex, with respect to any education program or activity) receiving Federal financial assistance. In addition, Executive Order 11141 prohibits discrimi­ nation on the basis of age by contractors and subcontractors in the performance of Federal contracts, and Executive Order WHAT IS NIGMS? The National Institute of General Medical 11246 states that no federally funded contractor may discriminate against any Sciences (NIGMS) supports basic research on genes, proteins and employee or applicant for employment cells. It also funds studies on fundamental processes such as how because of race, color, religion, sex, or national origin. Therefore, the programs of cells communicate, how our bodies use energy and how we the National Institute of General Medical Sciences must be operated in compliance respond to medicines. The results of this research increase our with these laws and Executive Orders. understanding of life and lay the foundation for advances in the Accessibility diagnosis, treatment and prevention of disease. The Institute’s This publication can be made available DEPT OF HEALTH AND HUMAN SERVICES in formats that are more accessible to research training programs produce the next generation of NATIONAL INSTITUTES OF HEALTH people with disabilities. To request this NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES scientists, and NIGMS has programs to increase the diversity of the material in a different format, contact the 45 CENTER DR RM 3AN.32 MSC 6200 NIGMS Office of Communications and BETHESDA MD 20892­6200 biomedical and behavioral research workforce. NIGMS supported Public Liaison at 301­496­7301; send e­mail to [email protected]; or write OFFICIAL BUSINESS the research of most of the scientists mentioned in this booklet. to the office at the following address: PENALTY FOR PRIVATE USE $300 45 Center Drive MSC 6200, Bethesda, MD 20892­6200. If you have questions or comments about this publication, you can use the same contact information to reach the office. Additional Copies and Web Links To order additional copies of The New Genetics or other free NIGMS publications, go to http://publications.nigms.nih.gov/order NATIONAL INSTITUTES OF HEALTH or use the contact information above. NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES OFFICE OF COMMUNICATIONS AND PUBLIC LIAISON The New Genetics is available online 45 CENTER DR RM 3AN.32 MSC 6200 at http://publications.nigms.nih.gov/ BETHESDA MD 20814­9692 thenewgenetics. Produced by the Office of Communications and Public Liaison National Institute of General Medical Sciences National Institutes of Health U.S. Department of Health and Human Services The New Genetics NIH Publication No.10 ­ 662 Revised April 2010 http://www.nigms.nih.gov Contents FOREWORD 2 CHAPTER 1: HOW GENES WORK 4 Beautiful DNA 5 Copycat 8 Let’s Call It Even 9 Getting the Message 11 Nature’s Cut­and­Paste Job 14 All Together Now 16 Genetics and You: Nursery Genetics 17 Found in Translation 18 RNA Surprises 19 An Interesting Development 20 The Tools of Genetics: Mighty Microarrays 22 CHAPTER 2: RNA AND DNA REVEALED: NEW ROLES, NEW RULES 24 RNA World 25 Molecular Editor 26 Healthy Interference 29 Dynamic DNA 30 Secret Code 30 Genetics and You: The Genetics of Anticipation 32 Battle of the Sexes 33 Starting at the End 34 The Other Human Genome 36 The Tools of Genetics: Recombinant DNA and Cloning 38 CHAPTER 3: LIFE’S GENETIC TREE 40 Everything Evolves 40 Selective Study 42 Clues from Variation 43 Living Laboratories 46 The Genome Zoo 52 Genes Meet Environment 53 Genetics and You: You’ve Got Rhythm! 56 Animals Helping People 58 My Collaborator Is a Computer 58 The Tools of Genetics: Unlimited DNA 60 CHAPTER 4: GENES ARE US 62 Individualized Prescriptions 64 The Healing Power of DNA 65 Cause and Effect 67 Us vs. Them 68 Genetics and You: Eat Less, Live Longer? 69 Gang Warfare 70 The Tools of Genetics: Mathematics and Medicine 72 CHAPTER 5: 21ST­CENTURY GENETICS 74 No Lab? No Problem! 76 Hard Questions 78 Good Advice 80 Genetics and You: Crime­Fighting DNA 81 Genetics, Business, and the Law 82 Careers in Genetics 85 The Tools of Genetics: Informatics and Databases 86 GLOSSARY 88 Foreword And every living thing Consider just three of Earth’s inhabitants: does one thing the same a bright yellow daffodil that greets the way: To make more of itself, it first copies its spring, the single­celled creature called molecular instruction manual—its genes—and then passes this infor­ Thermococcus that lives in boiling hot mation on to its offspring. This cycle has been springs, and you. Even a science­fiction repeated for three and a half billion years. But how did we and our very distant rela­ writer inventing a story set on a distant tives come to look so different and develop so many different ways of getting along in the planet could hardly imagine three more dif­ world? A century ago, researchers began to answer ferent forms of life. Yet you, Thermococcus that question with the help of a science called genetics. Get a refresher course on the basics in and the daffodil are related! Indeed, all of Chapter 1, “How Genes Work.” It’s likely that when you think of heredity the Earth’s billions of living things are kin you think first of DNA, but in the past few years, to each other. researchers have made surprising findings about The New Genetics I Foreword 3 another molecular actor that plays a starring role. Can DNA and RNA help doctors predict Check out the modern view of RNA in Chapter 2, whether we’ll get diseases like cancer, diabetes or “RNA and DNA Revealed: New Roles, New Rules.” asthma? What other mysteries are locked within When genetics first started, scientists didn’t the 6 feet of DNA inside nearly every cell in our have the tools they have today. They could only bodies? Chapter 4, “Genes Are Us,” explains what look at one gene, or a few genes, at a time. Now, researchers know, and what they are still learning, researchers can examine all of the genes in a liv­ about the role of genes in health and disease. ing organism—its genome—at once. They are Finally, in Chapter 5, “21st­Century doing this for organisms on every branch of the Genetics,” see a preview of things to come. Learn tree of life and finding that the genomes of mice, how medicine and science are changing in big frogs, fish and a slew of other creatures have ways, and how these changes influence society. many genes similar to our own. From metabolism to medicines to agriculture, So why doesn’t your brother look like your the science of genetics affects us every day. It is dog or the fish in your aquarium? It’s because of part of life … part of your life! evolution. In Chapter 3, “Life’s Genetic Tree,” find out how evolution works and how it relates to genetics and medical research. C H A P T E R 1 How Genes Work eople have known for many years that Proteins do many other things, too. They Pliving things inherit traits from their parents. provide the body’s main building materials, That common­sense observation led to agricul­ forming the cell’s architecture and structural ture, the purposeful breeding and cultivation of components. But one thing proteins can’t do is animals and plants for desirable characteristics. make copies of themselves. When a cell needs Firming up the details took quite some time, more proteins, it uses the manufacturing instruc­ though. Researchers did not understand exactly tions coded in DNA. how traits were passed to the next generation The DNA code of a gene—the sequence of until the middle of the 20th century. its individual DNA building blocks, labeled A Now it is clear that genes are what carry our (adenine), T (thymine), C (cytosine) and G traits through generations and that genes are (guanine) and collectively called nucleotides— made of deoxyribonucleic acid (DNA).
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