Angelina Jolie just became part of a medical trend: More women are deciding to have their breasts removed to reduce the risk of cancer.
Over the past decade, doctors have noticed a big increase in the number of women choosing prophylactic, or preventive, mastectomies.
Some, like Jolie, have a genetic mutation that makes it much more likely that they will have breast cancer. Her mother died of the disease at age 56. Jolie is 37. She wrote about her decision in The New York Times.
A study of genetically identical mice is providing some hints about humans. How can one identical twin be a wallflower while the other is the life of the party?
The study of 40 young mice found that their behavior grew increasingly different over three months, even though the mice shared the same genes and lived in the same five-level cage, researchers report Thursday in the journal Science.