Cancer Support

Hereditary Cancer & Genetics

Cancer is usually caused by gene mutations that occur randomly in one or a few cells of the body. Such gene changes, called somatic mutations, may arise as a natural consequence of aging or when a cell’s DNA has been damaged. Acquired mutations are only present in some of the body’s cells, and they are not passed on from parents to their children.

However, in a small percentage of people with cancer, the disease is due to a different type of mutation called a hereditary mutation, or germline mutation. These mutations are usually inherited from one or both of the person’s parents, and are present in nearly every cell of the body. Because hereditary mutations are present in the DNA of sperm and egg cells, they can be passed down in families.

People who carry such hereditary mutations do not necessarily get cancer, but their risk of developing the disease at some point during their lifetime is higher than average.

In recent years, scientists have discovered a number of mutations that can contribute to a person’s risk of developing certain cancers, including breast, ovarian, colorectal, and prostate cancer, as well as some other, less common cancer types.