We all carry the same genes.  Some of those genes are responsible for cell division in certain areas of our bodies. Risky gene mutations greatly affect the carrier's ability to ward off or fightbreast, ovarian and prostatecancer. Depending on the mutation carried, a person may also be at slightly higher risk of some other types of cancer.. 

Each child of a carrier has the same 50/50 chance of inheriting the same gene mutation as their carrier parent.

The way we inherit genes explains why it is important to look at the history of cancer on both sides of a family. A woman can inherit an increased risk of breast cancer or ovarian cancer from her father in the same way that she can inherit it from her mother. Alternately, a man can inherit an increased risk of prostate and breast cancer from his mother the same way he can from his father.  

Learn more about how risky genes cause cancer

Hereditary breast, ovarian and prostate cancer is far more common that most people think.An estimated 5-25% of these cancers are known to be hereditary, which translates to 3-5 times more people than are affected by multiple sclerosis. When considering the other cancers risky gene carriers are also susceptible to, plus the portion of carriers that aren't expected to be diagnosed with cancer, the incidence is even higher.

Certain ethnic groups have a much higher chance of carrying risky genes. For example, people of Ashkenazi (Eastern European) Jewish ancestry have a 1 in 40 chance of carrying one of three founder BRCA risky gene mutations associated with that population.  Other ethnic groups include, but are not limited to: French Canadian, Bahamian, Polish, Icelandic and African American.

Many genes have been discovered that, if mutated, fall under the HBOC syndrome umbrella.  Researchers suggest only about half of this hereditary cancer has been explained, leaving more risky genes to be discovered.

Most of the research that drives today’s medical recommendations is based only on what is known about the BRCA mutations.  With more than 1,200 different types of mutations discovered to date in just in each BRCA gene, researchers do not yet have enough information to stratify cancer risk for each of those specific mutations or to give a definitatve picture regarding cancer risk for mutations in the other risky genes.   As a result, cancer risk data  tends to be reported in average ranges, and  may differ depending on the source.  It is important to understand that personal cancer risk may fall above or below the averages ranges shown.

In addition to the type of risky gene an individual carries and the specific mutation within that gene, certain other factors may further increase cancer risk, including:
■ previous breast biopsies (especially if the biopsy showed atypical cells or Lobular Carci-noma in Situ (LCIS))
■ having dense breast tissue
■ number of first-degree relatives with cancer
■ young onset of menarche
■ very high exposure to radiation
■ absence of a healthy lifestyle

Personal cancer risk assessments are based on a variety of factors. It is essential that cancer risk be assessed by a trained genetics professional

Cancer Risk