The BSE benchmark Sensex gained nearly 69 points in opening trade today.The 30-share Sensex, which has lost 623.17 points in the past four sessions, recovered by 68.79 points, or 0.44 per cent, to 15,448.13 in opening trade today.In a similar fashion, the wide-based National Stock Exchange Nifty index moved up by 24.15 points, or 0.27 per cent, to 4,637.25.