Yes and no. Some diseases, such as cystic fybrosis, sickle cell anemia, and hemochromatosis, are purely genetic. Most, however, are a combination of genetic makeup and environmental factors. You aren't born with the condition; you only inherit a predisposition or tendency to develop the disease. This doesn't guarantee that you will, however. Alcoholism, for example, has been show to have a genetic component, but the child of an alcoholic will not automatically develop alcoholism. Other examples of diseases for which you may inherit a genetic predisposition include heart disease, diabetes, breast cancer and alzheimer's disease.

To learn whether you may have any genetic predispositions to disease, it is important to create a family medical history. By knowing your risk, you can make informed decisions about prevention and screening, and even participate in genetic-based research aimed at understanding, preventing and curing disease. It can literally save your life!