Britain\'s top shares edged lower on Wednesday, tracking falls on Wall Street and in Asia on concerns over the global growth outlook, although gains in heavyweight miners and banks provided a floor under the FTSE 100 index around the 5,800 level, according to Reuters. At 0805 GMT, the FTSE 100 index was down 12.45 points or 0.2 percent at 5,797.80, having shed 0.5 percent on Tuesday after the International Monetary Fund issued a downbeat view on global economic growth. There does not seem to be a great deal of conviction in the market ... There are a whole range of factors driving the market in the background, potentially one way or the other, with the results season just adding a touch of nerves after Alcoa\'s outlook downgrade,\' said Keith Bowman, equities analyst at Hargreaves Lansdown.