研究所、轉學考(插大)、學士後-英文題庫下載題庫

        Angelina Jolie’s chances of developing breast cancer were so high because she inherited a mutated BRCA 1 gene from her mother, Marcheline Bertrand, who died of ovarian cancer at the age of 56. The BRCA1 is present in everyone but only mutates in one in 1,000 people. Anyone with the mutation has a 50-80% chance of developing breast cancer. But Jolie’s risk figure was calculated to be even higher because of other factors, including family history. 

        “There are various computer programs where you can input genetic information, family history and other things and it will calculate a figure, which is why she’s got this very precise sounding number,” says Dr. Kat Arney, a senior science manager at Cancer Research UK. 

        Breast cancer is already “the top cancer in women both in the developed and the developing world”, according to the World Health Organization - and in many countries, it’s becoming more common. Overall, a woman living in the UK has a 12% chance of getting breast cancer during her lifetime. It’s the same in the US. But increasing longevity isn’t the only reason for the high incidence of breast cancer. 

        “There is an increase in rates in younger women and it’s for a number of reasons. We know that women’s lifestyles are changing and being overweight and drinking a lot of alcohol is linked to breast cancer risk,” says Arney. 

        Changes in reproductive habits are also a factor. According to Cancer Research UK, the relative risk of developing breast cancer is estimated to increase by 3% for each year an adult woman delays becoming a mother. Women who breastfeed also reduce their risk. The longer a woman breastfeeds, the greater the protection. It’s estimated that risk is reduced by 4% for every 12 months of breastfeeding. This may explain why women in richer countries have a higher risk of breast cancer. African women are four times less likely to get the disease because they have children at a younger age, have more of them and breastfeed them for longer.