The Bombay Stock Exchange benchmark Sensex on Friday gained 55 points to 17,640 in early trade. The wide-based National Stock Exchange index Nifty rose by 20 points at 5,280 points at the same time. The sensex was trading 11 points down a short while ago.The Dow Jones Industrial Average had gained 0.1 per cent to 10,691 and the Nasdaq Composite was also up 0.1 per cent higher at 2,311.