Researchers have invented a silicone chip that could make genetic analysis far more sensitive, rapid, and cost-effective by allowing individual cells to fall into place like balls in a pinball machine. The device — about the size of a nine-volt battery — allows scientists to simultaneously analyze 300 cells individually by routing fluid carrying cells through microscopic tubes and valves. By facilitating such “single-cell analysis,” the device could accelerate genetic research and hasten the use of far more detailed tests for diagnosing cancer.