Is cancer inherited?
Usually cancer is not inherited. However, some people are born with an increased risk of cancer because they inherit an altered gene important for cell growth or for repair of damaged DNA, for example. Scientists have already identified some of the gene alterations that predispose some people to various types of cancer, such as breast, ovarian and colon cancer. In 2009 a baby was born after having been screened alongside other embryos to ensure she was free of the mutated BRCA1 gene linked to hereditary breast cancer.
What do we know about bowel cancer?
Most bowel cancer is not inherited and is found more frequently in people who have low-fibre, high-fat diets. However, 5-10% of affected people do have an inherited form of the disease. Scientists have identified several genes involved in hereditary bowel cancer. These genes normally make proteins that repair damage to other genes, preventing abnormal cell growth. A person who inherits a changed form of any of these genes has a high risk of developing bowel cancer, regardless of their diet and lifestyle.
What do we know about breast cancer?
Breast cancer is the most common cancer in the UK. In most cases, a family history of the illness does not mean it is inherited. But 5-10% of affected women do have an inherited form of the disease, usually with earlier onset. Scientists have identified two genes that are altered: BRCA1 and BRCA2. These genes normally make proteins that repair DNA damage, preventing abnormal cell growth. A woman who inherits a changed version of either of these genes has a high risk of developing breast cancer.