Lauran Neergaard

Cancer patients often wonder “why me?” Does their tumor run in the family? Did they try hard enough to avoid risks like smoking, too much sun or a bad diet? Lifestyle and heredity get the most blame but new research suggests random chance plays a bigger role than people realize: Healthy cells naturally make mistakes when they multiply, unavoidable typos in DNA that can leave new cells carrying cancer-prone genetic mutations. How big? About two-thirds of the mutations that occur in various forms of cancer are due to those random copying errors, researchers at Johns Hopkins University reported Thursday...

A tool to edit human genes is nowhere near ready to use for pregnancy — but altering early embryos as part of careful laboratory research should be allowed as scientists and society continue to grapple with the ethical questions surrounding this revolutionary technology, organizers of an international summit say. “It would be irresponsible” to edit human sperm, eggs or early embryos in a way that leads to pregnancy, said Nobel laureate David Baltimore of the California Institute of Technology, who chaired the summit, which ended Thursday. Tools to precisely edit genes inside living cells, especially a cheap and easy-to-use one called CRISP-Cas9,...

WASHINGTON – Twitter confirms it: People tend to wake up in a good mood and are happiest on weekends. The fast-paced forum is offering scientists a peek at real-time, presumably little-filtered human behavior and thoughts. Cornell University researchers turned to the microblog to study mood and found a pretty consistent pattern. The researchers analyzed English-language tweets from 2.4 million people in 84 countries, more than 500 million of the brief, conversation-like exchanges sent over two years. They used a computer program that searched for words indicating positive mood – happy, enthusiastic, brilliant – or negative mood – sad, anxious,...