Your mother or sister has just told you she tested positive for a mutation in one of her BRCA genes, meaning her risk of getting breast or ovarian cancer is much higher than normal. And there is a 50 percent chance you have the same mutation.

Do you get yourself tested?

All too often, the answer is no, according to a new study by researchers at Fox Chase Cancer Center.

The authors interviewed 438 close relatives of 253 women who had shared results of their tests for cancer-causing mutations in the genes, called BRCA1 and BRCA2.

Among the relatives of women with mutations, just 52 percent said they intended to get tested themselves.

And when women revealed that they did not have a mutation but still another family member was known to have one - just 36 percent of relatives hearing about the results said they would pursue testing.

Study author Mary B. Daly, chair of Fox Chase's clinical genetics department, said the findings were a reminder that clear communication is paramount.

"If they don't intend to pursue testing, either they really don't understand what it means for them, or they're sort of in denial," Daly said of the relatives.

Daly said a possible solution is for doctors and counselors to offer to explain a woman's test results directly to her close relatives. She and colleagues are evaluating that approach.

The study results were presented Thursday at the San Antonio Breast Cancer Symposium. Other authors of the study included Fox Chase's Susan Montgomery, Ruth Bingler, and Karen Ruth.

Comprehension of test results is not the only issue. Some family members did not get the chance.

A larger, initial pool of 422 tested women shared their results with just 80 percent of eligible relatives.

Women with one of the telltale BRCA mutations have a 40 percent to 85 percent risk of getting breast cancer at some point, depending on whether it is in the BRCA1 or BRCA2 gene, among other variables, Daly said. And those kinds of breast cancers tend to strike earlier in life.

And women with one of the BRCA mutations have a 15 percent to 40 percent chance of getting ovarian cancer.

Mutations in the BRCA genes account for 5 percent to 10 percent of all breast cancers and 15 percent of ovarian cancers.

The Fox Chase study did not look at whether the relatives actually followed through and got tested, but Daly acknowledged some may not have done so.

The test is expensive - costing up to $4,000 when checking for the full range of possible mutations, Daly said - and is not always covered by insurance.

It was previously offered by just one company, Myriad Genetics. But with a Supreme Court ruling this year that disallowed patents on naturally occurring human genes, multiple companies are offering tests for these and other breast cancer-related mutations, Daly said.

"We're hoping competition will drive it down some," Daly said of the cost.