What is Genetics? : Frequent Questions & Answers

Are diseases caused by any other factors other than changes in genes?

Nearly all diseases are cause by a combination of both genes and environment. Genetic research has lead to the discovery of many genes that contribute to a person’s risk for getting diseases like Alzheimer disease, diabetes, autism, cancer, and heart disease. However, the genes aren’t the whole story! It also has been discovered that a person’s environment such as their diet, how much they exercise, stress level, and habits also contribute to these diseases. Because of the interaction of all these factors, these diseases are often called complex diseases. While complex diseases can run in a family, they may not follow a particular pattern. For example, there may be a gene that is being passed through a family that causes a high risk for heart disease. This gene only increases a person’s chance of getting heart disease, but does not necessarily cause the disease. This means that even if a person inherits this “risky” gene, they may not develop heart disease, especially if they follow a healthy diet and exercise regularly.

Complex diseases can be hard to understand and predict. It can be helpful to know if someone has genetic risk factors for a complex disease so that the person can change their lifestyle. For example, a person who has is at high risk for diabetes may be advised by their doctor to change their diet, monitor their blood sugar, or exercise regularly. This may help to prevent that person from developing diabetes, even though they are predisposed to the disease. One way to find out if someone is at high risk for a complex disease is to look at their family health history. Learn more by visiting Complex Disease.