BRCA1 and BRCA2
Risks associated with inherited alterations in BRCA1 or BRCA2
BRCA1 and BRCA2 are two examples of genes that works to prevent cancer by correcting specific types of DNA damage. Inherited alterations in either of these two genes greatly increase the risk of cancer; particularly cancer of the ovary, breast and prostate. Rarely, other cancers, such as melanoma, pancreatic, or other cancers, have also been reported in individuals with BRCA1 or BRCA2 gene alterations.
The exact risk of cancer in an individual with an inherited BRCA gene alteration depends on a number of different features, including:
BRCA gene alterations are not associated with risks of cancer in childhood years
Most cancers in women with BRCA alterations are diagnosed after the age of 30
Most cancers in men with BRCA alterations are diagnosed after the age of 40
Gene in which alteration is identified
BRCA1 -v- BRCA2
Specific Genetic alteration
Where alteration is located in the gene
Number and type of cancers in the family
Age of onset of cancer in the family
Other Genetic Risk Factors
other inherited risk factors
Examples include use of Hormone Replacement Therapy, contraception
e.g. alcohol consumption, weight, family planning
Other factors (unknown)
Carriers of BRCA1/BRCA2 alterations
If a woman is found to have inherited an alteration in BRCA1 or BRCA2, there are steps she can take to minimise your likelihood of developing cancer of the breast or ovary. If a man is found to have inherited an alteration in either of these genes, he may also be at risk of developing male breast cancer or prostate cancer, and may, in turn, pass the alteration on to his own children.
How are BRCA gene alterations inherited?
We each have two copies of each of these genes, one of which we inherit from our mother, and the other from our father.
If you have inherited a BRCA gene alteration, each of your children (male or female) and each of your siblings (male or female) have a 50% (1 in 2) risk of inheriting the same alteration, as the video here below explains.