Assess Your Risk
If you have Ashkenazi Jewish heritage (on both sides of your family), your basic risk of carrying a BRCA gene is 1 in 40. It’s important to know that only 50% of people who carry a BRCA gene have a family cancer history that would indicate high risk. Some people have unknown risks due to limited knowledge of family history (e.g. from adoption or donor egg/sperm), small family size, or family where the majority of members have been biologically male. In the cases where even partial family history is known, there are ways to better understand your risk of carrying a BRCA gene, including mapping out your family medical history.
This information can also be helpful when you speak to your family doctor about getting tested for BRCA.
How to map out your family medical history
(adapted from the article by Karen Lu, MD)
Find out your ancestry. Include countries of origin and which members of the family have Ashkenazi Jewish heritage.
List blood relatives ONLY or create a basic blood relative family tree (see image). Include your first-degree relatives (parents, siblings, children) and second-degree relatives (nieces, nephews, aunts, uncles, grandparents). Add the current age of each person or the age when they died.
Add cancer diagnoses, if any. Include the age when they were diagnosed with cancer, if possible. List details, such as the part of the body where the cancer started.
Highlight any members of the family with cancer diagnoses. Use the same colored marker for each person with a diagnosis. This can be helpful for noticing a pattern in the genetic history.
Tools to help
Sharsheret’s Family Tree Chart can be helpful for taking notes on each family member in the history.
The Surgeon General’s Office Family Health Portrait online tool can help track all family-related diseases, not just cancer.
BC Cancer also offers a family diagram to help you map out your cancer risk.
Dig deeper for details
Hit a dead end while mapping out your tree? Try these tips to get more information:
Speak with older relatives. They are usually good sources of information.
Gather hospital records when there is some uncertainty.
Hospitals can release records directly to the patient.
If a relative has died, Hospitals can release records to the next of kin, the closest relative(s) entitled to the deceased individual’s property.
Keep an eye out for “yellow flags”
After completing your family tree, look for these “yellow flags,” which may indicate that you should speak with your doctor. He or she may recommend that you see a genetic counselor.
A family member diagnosed with cancer before age 50.
A family member who has had 2+ different cancers.
2+ family members who have had the same type of cancer. Look specifically for breast, ovarian, colorectal, prostate, or endometrial cancers.
