Indexes turn negative as Wall Street churns

NEW YORK (Reuters) - U.S. stock indexes turned negative on Wednesday, giving up earlier gains, as investor concerns lingered over how soon central banks will begin to scale back supportive measures.

The Dow Jones industrial average edged down 12.14 points, or 0.08 percent, at 15,109.88. The Standard & Poor's 500 Index slipped 1.29 points, or 0.08 percent, to 1,624.84. The Nasdaq Composite Index was off 6.03 points, or 0.18 percent, to 3,430.92.

(Reporting by Leah Schnurr; Editing by Bernadette Baum)