Cancer is a disease of the genome, caused by unchecked cell growth due to mutations or changes in our DNA. Cancer genomics involves studying the genetic changes in cancer cells, allowing us greater insight into prevention, early detection, treatment, prognosis and recurrence.
In the case of cancer, a change is introduced which causes the cells to multiply uncontrollably – they become cancer cells and allow a cancer to develop. Most of the time these cancer-causing genetic changes are acquired i.e. they occur from damage to genes in a particular cell during a person’s life (also known as sporadic cancer).
Why does cancer run in families?
Around 5-10% of cancers are caused by inherited or germline changes. This is where a genetic alteration occurs in a sperm or egg cell. It passes from the parent to the child at the time of conception and the alteration in the initial egg or sperm cell is copied into every cell within the body.
As the genetic alteration affects reproductive cells it can pass from parent to child and onwards to subsequent generations. Conditions such as Lynch Syndrome, is an example of an inherited cancer syndrome. This dominantly inherited conditions can greatly increase an individuals risk of developing cancer and mean that there is a 50% (or 1 in 2) chance that a parent can pass the genetic alteration onto their child.
Identifying a person with an inherited form of cancer is important. It means they can be looked after more closely in the future but it also has important implications for the family.
Genomics allows us to develop more precise treatments for cancer. Targeting treatments that focus on a cancer’s genetic makeup rather than where it has grown in the body.
Lynch Syndrome Ireland 