Facebook says the chancellor of the University of California at San Francisco, Susan Desmond-Hellmann, will join its board of directors.

She will be the second woman elected to the Menlo Park, Calif., company's board, joining Facebook's No. 2 executive, Sheryl Sandberg. The company named Sandberg to the body last June after criticism that its directors were all men.

Before serving as chancellor, Desmond-Hellmann was an executive at biotechnology drugmaker Genentech, which markets some of the best-selling in the world. She is a doctor with a specialty in treating cancer.

Facebook Inc.'s board also includes . chief Reed Hastings, entrepreneurs Marc Andreessen and Peter Thiel, and Washington Post Co. CEO Donald Graham. CEO and founder Mark Zuckerburg is chairman of the board.