DALLAS -- One of those quick cheek swabs to determine your ancestry may identify your risk for a specific breast cancer.

A new genetics study published in the journal Cancer looks at the link between ethnicity and triple-negative breast cancer. That’s one of the most aggressive forms of breast cancer -— tough to treat and beat.

“Three weeks ago, I had my seventh reconstruction surgery,” said Brianna Hinojosa-Flores, who is close to celebrating her three-year anniversary of being cancer-free.

“I actually have no family history, and that's why it was a complete shock,” said Hinojosa-Flores, who was diagnosed with triple-negative breast cancer, which is most prevalent in young Black and Latina women.

Brianna Hinojosa-Flores

“My mom was born in Mexico; my dad here in the United States, but of Mexican descent,” Hinojosa-Flores said. The mother of two is part of a small, three-year study at UT Southwestern about ethnicity and triple-negative breast cancer.

“One of the things that I was wondering was, is there some commonality amongst these different ethnic groups of women that we're just not seeing?” said Dr. Roshni Rao, surgical oncologist at UTSW.

Dr. Rao studied the mitochondrial DNA of 92 triple-negative cancer patients.

“Mitochondrial DNA is passed along the maternal line, so you can only get it from your mother,” Dr. Rao said, “and her mother only got it from her mother."

Dr. Roshni Rao

That allows cancer researchers to trace back several generations. The study found 13 percent of the women studied were unaware of their actual ancestry.

“My 30 patients who thought they were Hispanic -- 26 percent were actually some other ethnicity, either African-American or Ashkenazi Jewish ethnicity,” Rao said.

Her study also offers a surprise about people with ancestral roots in West African countries Nigeria, Sierra Leone, and Cameroon.

“We know that those populations are at higher-risk of triple-negative breast cancer, so perhaps your screening needs to be a little bit different than the average person,” Dr. Rao said.

Hinojosa-Flores, whose children are ages 7 and 11 expressed curiosity about her ancestry swab results. But that’s kept concealed as part of the study.

“The only question is how much of a risk does that give you for this cancer -- and that I just don't know yet,” Dr. Rao said, adding that a larger study will be needed to determine that.

The testing in the study was conducted using a simple swab.

There are commercially-available tests you can do online. Those aren’t medical lab tests, but Dr. Rao said they are a good start.