The only genetic testing clinic in the Maritimes has been busy answering calls for the past two days since actress Angelina Jolie announced she had a preventative double mastectomy.

A genetics test revealed Jolie, 37, carried a mutated gene that made it extremely likely she would develop breast cancer, according to an op-ed piece she wrote for the New York Times.

Pat Steele, a genetic counsellor at the IWK Health Centre's Maritime Medical Genetics Service in Halifax, says genetic testing can be a lengthy process.

"It's not an overnight thing for sure," said Steele.

"And it's very different if people look at the [United] States, where they do commercial testing and make a lot more money. There's a lot more resources put into that," she said.

"There's very few labs that do this testing. And it's quite a big test. It's not like taking a blood sample and then, you know, getting an iron level and getting it back in a few days."

Genetics is the study of how specific characteristics and diseases can develop in an individual and potentially be passed on to future generations.

It can take several months to be assessed and several more to have the blood samples tested, said Steele.

She encourages any patients considering generic testing to speak to their doctor first.

"Most people do not need a genetic test," said Steele. "There's only going to be about five to 10 per cent of individuals that are in a family where there's a genetic change they've inherited."

Jolie, an Oscar-winning actress and partner to Brad Pitt, decided to have the testing after watching her mother, actress Marcheline Bertrand, die at age 56 from cancer, according to the op-ed piece.

She learned she carries the "faulty" BRCA1 gene and had an 87 per cent chance of getting the disease.

So she underwent three months of surgical procedures to remove both breasts, with thoughts of her six children in mind, she wrote.