人类基因组计划--关于你的基因.pdf

There are more than 6 billion people on our planet — each a massive collection of about What’s 100 trillion cells. a How do these cells know what to do? What Genome? tells them to work together to keep your heart pumping, brain thinking and bones growing? The answer lies in a long, winding molecule called deoxyribonucleic acid, or DNA. The DNA contained within each of your cells carries the instructions needed to build and maintain the many different types of cells that make you, you. Researchers call this complete set of DNA instructions a “genome.” Is my genome unique? Humans come in many shapes and sizes, but we’re all very similar at the DNA level. In fact, the genomes of any two people are more than 99% the same. Still, the tiny fraction of the genome that varies among humans is very important. DNA variations are part of what makes each of us unique. They affect the color of your eyes, hair and skin. What’s more, they influence your risk of disease and your response to drugs. So, is everything determined by my genome? No, your DNA is just one part of the amazing puzzle of who you are. When it comes to your health, other pieces of the puzzle include lifestyle and environmental factors, such as the food you eat and the air you breathe. Once we learn more about how the human genome interacts with these factors to cause disease, we may be able to change our habits and adapt our environment to improve our health. Our genomes also are likely to contribute to some of the ways we feel, think and act. B