Family history is one factor that determines your breast cancer risk. One in eight women will be diagnosed with breast cancer in her lifetime. But a woman’s risk can be higher for a number of different reasons.

“It is important for women to be aware of their personal risk of breast cancer,” says Dr. Sandra Templeton, breast surgeon at Houston Methodist.

Here are the top four breast cancer risk factors.

1. Your age

The majority of women diagnosed with breast cancer are older than age 50, and the risk increases as you age. Two out of every three invasive breast cancers found are in women at least age 55.

2. Your ethnic background

Asian, Native American and Hispanic women are less likely to develop breast cancer. Caucasian women are more likely to be diagnosed, and African-American women are at greater risk of dying from breast cancer. An Ashkenazi Jewish ancestry also poses a higher risk.

3. Your family tree

Your breast cancer risk is doubled if your mother, sister or daughter has had the disease. But, you can still get breast cancer even without a family history. Fewer than 15% of women diagnosed with breast cancer have a family history of the disease. (Related: Cancer Genetic Counseling: Can Hereditary Cancer Be Prevented?)

4. Your genes

A woman who has the BRCA1 or BRCA2 gene mutation is at higher breast cancer risk — by as much as 87% — and for ovarian cancer, too.

“The goal is to find the mutation in women before they develop cancer,” Dr. Templeton says. “A simple blood or saliva test is meant to tell a woman whether she’s at high risk.”

Your doctor may recommend genetic testing, which looks for altered BRCA genes and other mutations, if your personal and family history warrants it. The results can help your doctor determine whether you would benefit from preventive surgery, additional screenings or medications to reduce your cancer risk.

Talk to your doctor if you have a family history of:

• Breast cancer before or at age 50
• Ovarian cancer at any age
• Male breast cancer at any age
• Ashkenazi Jewish ancestry and a personal or family history of breast or ovarian cancer
• Two breast cancers in the same person or on the same side of the family
• Triple-negative breast cancer before or at age 60
• A previously identified BRCA1 or BRCA2 mutation in the family