In May, actress Angelina Jolie stunned the world when she revealed that she'd undergone a preventive double mastectomy after genetic testing showed she was at a high risk for developing breast and ovarian cancer.

Since her disclosure, there has been a marked increase in genetic testing at treatment centers across the country, according to the National Society of Genetic Counselors. The increase is being called "the Angelina Jolie effect," although one doctor sees it a bit differently.

Angelina Jolie's Double Mastectomy Fueling National Debate

"I really think of it as the Angelina gift, it is really kicking up the whole conversation," said Dr. Marisa Weiss, director of breast health outreach at Lankenau Medical Center in Wynnewood, Pa., and president and founder of Breastcancer.org.

Angelina Jolie Loses Aunt to Breast Cancer: Should You Get BRCA Gene Testing?

Jolie revealed in a New York Times Op-Ed she made her decision to have a mastectomy after discovering she carries the BRCA1 gene mutation, the single rare gene mutation that produces a high risk of developing cancer.

One in 800 to one in 1,400 women are carriers of this mutation and the BRCA 1 and BRCA2 gene mutations account for between five and 10 percent of all breast cancer cases, according to the National Cancer Institute.

As Breast Cancer Awareness Month kicks off today, the doctor who performed Jolie's double mastectomy, Dr. Kristi Funk, of the Pink Lotus Breast Cancer Center in Beverly Hills, is speaking out about what every woman should know about the BRCA gene mutation and breast cancer.

"Genetic testing is easily done through a blood sample or just a swish-and-spit with Scope," Funk said today on a special "go pink" edition of " Good Morning America."

Go Pink: Take ABC's Breast Cancer Pledge

"The question becomes difficult when you try to say who is appropriate for testing so that is where the education really needs to step up," said Funk, who also believes that many more people may carry a BRCA mutation than current estimates suggest. "Of all Americans, one million of us carry a BRCA1 mutation but it will take 19 million high-risk people to find the one million. And those 18 million people then who don't have BRCA1 are high enough risk to test."

Funk's Pink Lotus clinic offers a five-question assessment on its website that takes one minute to complete and determines if testing is right for you.

Click HERE to Take Pink Lotus' Risk Assessment Quiz

The genetic risks for the BRCA1 gene mutation, according to Funk, go all the way back to third generation relatives on both the maternal and paternal sides of a woman's family.

"What you're looking for is for one of those relatives to either have breast cancer prior to age 50 or ovarian cancer at any age," Funk said on "GMA." "Dad can pass this gene down too."

How to Reduce Your Breast Cancer Risk

According to Breastcancer.org, a number of steps can lower someone's breast-cancer risk immediately. Those include limiting alcohol intake, maintaining a healthy weight, exercising three to four hours per week and avoiding cooking in plastics.