FTSE shrugs off Greece downgrade

London's blue chip index rose 15 points to 5,957.51 just after the opening bell, driven up by defensives including energy giant Centrica and Imperial Tobacco. Gains came after it closed down 37 points on Monday in reaction to the latest downgrade of Greece's credit rating by S&P. The credit rating agency slashed the region's credit rating by two notches, from BB to B. A further downward move would make it the most lowly rated country in Europe. However, UK investors shrugged off the downgrade this morning, looking instead to overnight gains in the US where the S&P 500 closed up 0.5...