A woman with a faulty BRCA gene is up to 20 times more likely to get breast cancer than the average person is over a lifetime.
Going under the knife to remove her breasts and ovaries can slash the risk by up to 95 per cent.
That is why at least 15 women with the mutation have chosen to remove their ovaries and fallopian tubes at the National University Cancer Institute (NCIS) in the past five years - even though they did not have cancer.
Another seven patients opted to also remove their breasts as a preventive measure.
Such decisions came under the spotlight recently after United States actress Angelina Jolie announced that she had removed her ovaries and fallopian tubes because of a cancer scare last month.
She already had a double mastectomy in 2013, after discovering that she had a faulty BRCA gene, which makes her more likely to develop breast and ovarian cancer.
BRCA genes have various functions, such as maintaining stability when cells divide and repairing damaged DNA. When they mutate and DNA damage is not repaired, cancer is more likely to develop.
For one 62-year-old here who was screened at the National Cancer Centre Singapore (NCCS) and found she had inherited the mutation, deciding to remove her ovaries was an easy choice to make.
"It's very hard for any woman, but what is more important is your life," she said.
She got tested after her sister and mother were diagnosed with breast and ovarian cancer respectively. Now, she is worried for her three daughters, who could also carry the faulty gene. "Naturally, as a mother, I'm very concerned," she said. "But (being tested) is a personal decision for them to make."
Dr Lee Soo Chin of NCIS said that Jolie's high-profile operations had made testing for this gene more popular here.
The senior consultant said the "uptake rate among women recommended to consider BRCA testing was less than 20 per cent". After May 2013 - when Jolie announced her first surgery - the figure went up to 50 per cent.
People who might be asked to go for genetic testing include those with a strong family history of breast and ovarian cancer, or whose family members were diagnosed with cancer at a young age.
However, doctors point out that women who carry the faulty gene do not need to get preventive surgery immediately, and can wait until they have completed their families.
Some women take medicine to reduce the risk, while others opt for more frequent screening, said Dr Joanne Ngeow, who heads the cancer genetics service at NCCS.
This article was first published on April 6, 2015.
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