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Library of Congress Control Number: 2019954514
ISBN: 978-1-119-63303-7; ISBN (ePDF): 978-1-119-63308-2; ISBN (ePub): 978-1-119-63312-9
Genetics For Dummies®
To view this book's Cheat Sheet, simply go to www.dummies.com and search for “Genetics For Dummies Cheat Sheet” in the Search box.
Introduction
Genetics affects all living things. Although sometimes complicated and always diverse, all genetics comes down to basic principles of heredity — how traits are passed from one generation to the next — and how DNA is put together. As a science, genetics is a fast-growing field because of its untapped potential — for good and for bad. Despite its complexity, genetics can be surprisingly accessible. Genetics is a bit like peeking behind a movie’s special effects to find a deceptively simple and elegant system running the whole show.
About This Book
Genetics For Dummies, 3rd Edition, is an overview of the entire field of genetics. Our goal is to explain every topic so that anyone, even someone without any genetics background at all, can follow the subject and understand how it works. As in the first and second editions, we include many examples from the frontiers of research. We also make sure that the book has detailed coverage of some of the hottest topics that you hear about in the news, including gene therapy, pharmacogenetics, and gene editing. And we address the practical side of genetics: how it affects your health and the world around you. In short, this book is designed to be a solid introduction to genetics basics and to provide some details on the subject.
Genetics is a fast-paced field; new discoveries are coming out all the time. You can use this book to help you get through your genetics course or for self-guided study. Genetics For Dummies, 3rd Edition, provides enough information for you to get a handle on the latest press coverage, understand the genetics jargon that mystery writers like to toss around, and translate information imparted to you by medical professionals. The book is filled with stories of key discoveries and “wow” developments. Although we try to keep things light and inject some humor when possible, we also make every effort to be sensitive to whatever your circumstances may be.
This book is a great guide if you know nothing at all about genetics. If you already have some background, then you’re set to dive into the details of the subject and expand your horizons.
Conventions Used in This Book
It would be very easy for us to use specialized language that you’d need a translator to understand, but what fun would that be? Throughout this book, we try to avoid jargon as much as possible, but at the same time, we use and carefully define terms that scientists actually use. After all, it may be important for you to understand some of these multisyllabic jawbreakers in the course of your studies or your or a loved one’s medical treatment.
To help you navigate through this book, we use the following typographical conventions:
We use italic for emphasis and to highlight new words or terms that we define in the text.
We use boldface to indicate keywords in bulleted lists or the action parts of numbered steps.
We use monofont for websites and email addresses.
Foolish Assumptions
It's a privilege to be your guide into the amazing world of genetics. Given this responsibility, you were in our thoughts often while we were writing this book. Here’s how we imagine you, our reader:
You’re a student in a genetics or biology class.
You’re curious to understand more about the science you hear reported in the news.
You’re an expectant or new parent or a family member who’s struggling to come to terms with what doctors have told you.
You’re affected by cancer or some hereditary disease, wondering what it means for you and your family.
If any of these descriptions fit, you’ve come to the right place.
How This Book Is Organized
We designed this book to cover background material in the first two parts and then all the applications in the rest of the book. We think you’ll find it quite accessible.
Part 1: The Lowdown on Genetics: Just the Basics
Part 1 explains how trait inheritance works. The first chapter introduces you to the field of genetics and what genetics professionals may do in their day-to-day work lives. The second chapter gives you a handle on how genetic information gets divvied up during cell division; these events provide the foundation for just about everything else that has to do with genetics. From there, we explain simple inheritance of one gene and then move on to more complex forms of inheritance.
Part 2: DNA: The Genetic Material
Part 2 covers what’s sometimes called molecular genetics. Don’t let the word “molecular” scare you off. We give you nitty-gritty details, but we break them down so that you can easily follow along. We track the progress of how your genes work from start to finish: how your DNA is put together, how it gets copied, and how the building plans for your body are encoded in the double helix. To help you understand how scientists explore the secrets stored in your DNA, we also cover how DNA is sequenced. In the process, we relate the fascinating story behind the Human Genome Project.
Part 3: Genetics and Your Health
Part 3 is intended to help you see how genetics affects your health and well-being. We cover the subjects of genetic counseling; inherited diseases; genetics and cancer; and chromosome disorders such as Down syndrome. We also include a chapter on gene therapy, a practice that may hold the key to cures or treatments for many of the disorders we describe in this part of the book.
Part 4: Genetics and Your World
Part 4 explains the broader impact of genetics and covers some hot topics that are often in the news. We explain how various technologies work and highlight both the possibilities and the perils of each. We delve into population genetics (of both humans, past and present, and endangered animal species), evolution, DNA and forensics, genetically modified plants and animals, and the issue of ethics, which is raised on a daily basis as scientists push the boundaries of the possible with cutting-edge technology.
Part 5: The Part of Tens
In Part 5, you get our lists of ten milestone events and important people that have shaped genetics history, and ten of the next big things in the field.
Icons Used in This Book
All For Dummies books use icons to help readers keep track of what’s what. Here’s a rundown of the icons we use in this book and what they all mean.
This icon points out stories about the people behind the science and accounts of how discoveries came about.
This icon flags information that’s critical to your understanding or that’s particularly important to keep in mind.
These details are useful but not necessary to know. If you’re a student, though, these sections may be especially important to you.
Points in the text where we provide added insight on how to get a better handle on a concept are found here. We draw on our personal experience for these tips and alert you to other sources of information you can check out.
Beyond This Book
We’ve included a ton of extra content on the website that accompanies this book. To find it, simply open your favorite web browser, go to www.dummies.com, and search for Genetics For Dummies to find the following:
Cheat Sheet: We’ve created Cheat Sheet pages that review basic genetics terminology; the structure of cells, chromosomes, and DNA; the laws of inheritance; solving genetics problems; and the basics of transcription and translation.
Bonus chapters: While the book covers a lot of the hottest topics in genetics, it can’t cover everything. Check out the bonus chapter on cloning.
Updates to the book, if any.
Where to Go from Here
With Genetics For Dummies, 3rd Edition, you can start anywhere, in any chapter, and get a handle on what you’re interested in right away. We make generous use of cross-references throughout the book to help you get background details that you may have skipped earlier. The table of contents and index can point you to specific topics in a hurry, or you can just start at the beginning and work your way straight through. If you read the book from front to back, you’ll get a short course in genetics in the style and order that it’s often taught in colleges and universities — Mendel first and DNA second.
Part 1
The Lowdown on Genetics: Just the Basics
IN THIS PART …
Discover the basics of genetics and the various careers in the field.
Learn how cells divide and how chromosomes are divvyed up among those cells.
Learn about Mendelian genetics and how genes and traits are inherited.
Understand how the inheritance of genes and traits is not always straightforward.
This icon points out stories about the people behind the science and accounts of how discoveries came about.
This icon flags information that’s critical to your understanding or that’s particularly important to keep in mind.
These details are useful but not necessary to know. If you’re a student, though, these sections may be especially important to you.
Points in the text where we provide added insight on how to get a better handle on a concept are found here. We draw on our personal experience for these tips and alert you to other sources of information you can check out.