People who develop breast cancer before the age of 40 or have several family members with the disease are being urged to take a test to see if they have a type of gene mutation that can cause hereditary breast cancer. Detecting the condition, known as a BCRA gene mutation, can help those who are at risk but have not developed cancer detect and treat the disease at an early stage. The Hong Kong Sanatorium and Hospital set up the Comprehensive Oncology Centre in March, and launched a hereditary and high-risk breast cancer programme in collaboration with the Stanford University Medical Centre in the United States, as well as the two local medical faculties. Programme director Ava Kwong said the centre had so far conducted genetic testing for 69 breast cancer patients, of whom 18 were found to have the BCRA gene mutation. Half the 18 patients had developed breast cancer before the age of 45. Dr Kwong said 85 per cent of people with the BCRA mutation might develop breast cancer, while 51 per cent might develop ovarian cancer - 10 times and 50 times higher risk than the general population, respectively. The centre invited the families - especially members who do not have cancer - of the 18 breast cancer patients detected with the mutation to undergo the tests. In one case, a patient's brother was detected with the mutation but did not develop the cancer. However, his two daughters in their 20s also had the mutation. The doctors suggested they have regular mammogram and ultrasound tests, even though such tests are usually recommended for women over 40. Three other sisters of the patient also had breast cancer. In another case, a patient's son in his 20s was found with the mutation. 'We hope that genetic testing can keep the patients' family members under health surveillance early,' Dr Kwong said. 'Sometimes, people with the mutation may consider removing the breasts or ovary, especially those who are already in menopause, to prevent them from developing cancer.' Of the 18 patients with the mutation, the scientists found three novel BCRA mutations previously not reported. Joey Wong, 26, could hardly believe she had the disease when she was diagnosed in November. She underwent surgery in December and has not recovered. 'I was shocked because I was so young. My aunt died of breast cancer in her 40s, seven years ago. But I never thought I would follow suit,' she said.