The health care venture from Amazon, Berkshire and JP Morgan just hired its first female exec, and she comes from a big insurance company

The joint health care venture by Amazon, Berkshire Hathaway and J.P. Morgan has hired a well-known health insurance exec who specializes in analyzing data to improve patient health. The group has scooped up Dana Gelb Safran, formerly a chief performance measurement and improvement officer at Blue Cross Blue Shield of Massachussetts, CNBC has learned.