Xconomy -- Waltham, MA-based BG Medicine (NASDAQ: BGMD) started trading publicly today at $7 per share. After indicating earlier in the week that it had planned to offer 4.75 million shares in its initial public offering, the diagnostics company sold 5 million shares. Lazard Capital Markets acted as sole book-running manager for the deal, and underwriters will have the 30-day option to purchase an additonal 750,000 shares of common stock to cover over-allotments. BG shares had risen by more than 12 percent as of 2:19 pm EST, to hit $7.89 apiece.
