How is it done? 

This is a very simple test. 

First, a small blood sample is collected in a hospital or clinic and sent to a specialized laboratory.

In the laboratory the test can be done through different methods.

Most genetic tests look for changes in the normal DNA sequence of the gene that is being tested 

To learn how mutations are linked with cancer Biology of cancer

Other genetic tests do not look at the DNA, but instead at the proteins it produces. They analyze the length or the functionality of the protein, looking for abnormalities. 

In breast cancer, most tests look for changes in the DNA of the BRCA1 and the BRCA2 genes (BRCA = BReast CAncer genes), which are located, respectively, in chromosome 17 and 13.

Sometimes, in very particular cases, testing can also include the genes PTEN and TP53, which are associated with the Cowden and the Li-Fraumeni breast cancer syndromes. These are very rare though, accounting for less than 1% of all the hereditary breast cancers.

Due to their complexity, test results can take a few months.

next close
Know… the leaflets on the side effects of breast cancer therapies: how to manage problems, such as nausea and vomiting, or hair loss. (see)
Know… the interactive "familial history", allows the construction of a graphic with the history of breast cancer in your family. (see)
Know… more about cancer biology: what is a mutation and what promotes these changes in cells DNA? (see)
Know… What is a triple negative cancer? Drinking alcohol increases the risk of breast cancer? What is the anatomy of the breast? (see)
Know… what you know about familial breast cancer: complete our 7-question "expert " quiz. (see)
Know… more about sporadic breast cancer, and test your knowledge using our 7-question quiz. (see)
Know… the particularities of breast cancer in man: test your knowledge in our 7-question quiz (see)