Breast cancer genetic testing
Breast cancer can be hereditary. A simple genetic analysis can tell us more about this possibility
How can we help you?
What is breast cancer genetic testing?
One in every eight women will have breast cancer at some point in her life and there is a hereditary component to some of these cases. We can use genetics to analyse a person’s predisposition to breast cancer so that any necessary preventive measures can be taken.
What is breast cancer genetic testing used for? What is its purpose?
The majority of breast cancer cases are sporadic. In other words, the cancer is the result of a build-up of mutations over the course of a woman’s life and there is no hereditary component involved. In around 10% of cases, however, a hereditary predisposition to cancer does exist. The likelihood is increased by mutations in certain genes that are inherited from parents.
A third of all cases of hereditary breast cancers are caused by BRCA1 mutations, an additional third are caused by BRCA2 mutations and the rest are caused by other genes. Breast cancers linked to BRCA1 manifest during the pre-menopause (at an average age of 42) and the contralateral breast cancer rate after five years is around 30% in women who are carriers of the BRCA1 mutation. Abnormalities in gene BRCA2 are also linked to breast cancer in men.
What does breast cancer genetic testing entail?
IB Biotech has two different levels of BRCA1 and BRCA2 gene mutation analyses:
- Whole sequencing of the BRCA1 and/or 2 coding regions and analysis of deletions and duplications.
- An analysis of the most common mutations. The most prevalent mutations are analysed and in 50% of cases there is an abnormality in the following genes: *BRCA1: 187-188delAG; 330A>G; 5236G>A; 5242C>A and 589-590delCT. *BRCA2: 3036-3039del ACAA; 6857-6858delAA; 9254-9258del5; 9538-3539delAA and 5374-5377delTATG.
When is taking a breast cancer genetic test advisable?
Some of the situations in which having an analysis could prove useful are indicated below.
- Families in which there has been just one case of breast cancer.
- Primary bilateral breast cancer under 40 years of age;
- Breast cancer under 30 years of age;
- Breast and ovary cancer in the same patient.
- Families in which there have been two cases of cancer in first-degree relatives.
- Two diagnosed cases of breast cancer, in which at least one patient was under 50 years of age, or bilateral cancer;
- Two or more cases of ovary cancer;
- Cases of breast cancer and ovary cancer in two relatives;
- Breast cancer in a woman and breast cancer in a man.
- Families in which there have been three or more cases of breast cancer, at least two of which have been in first-degree relatives (mothers, daughters or sisters).