* TSX falls 48.13 points, or 0.38 percent, to 12,551.61 * Materials off 0.7 percent, financials down 0.36 percent By Solarina Ho TORONTO, Jan 11 (Reuters) - Canada's main stock index retreated on Friday after a disappointing quarterly report from Wells Fargo, the first major U.S. bank to post earnings, and a fall in mining stocks on softer commodity prices. Wells Fargo reported a record fourth-quarter profit but net interest margin declined and the bank made fewer mortgage loans than in the previous quarter. "I think probably the biggest highlight is the Wells Fargo, with their profit margins not being as strong as everyone was hoping. That put everybody in sort of a neutral mode," said Mike Newton, associate director and portfolio manager at Macquarie Private Wealth Inc. Newton said that U.S. earnings always impacts Canadian stocks and added that a chief technical analyst with SAC Capital Advisors saying the benchmark S&P 500 index has "topped out." "People pay a lot of attention to some of these indicators and that was a bit of a negative," he said. The TSX's own heavily weighted financial group was down 0.36 percent, led by the Toronto Dominion Bank's 0.62 percent fall to C$18.56. Bank of Nova Scotia was also among the top five most influential stock weighing on the index, giving back 0.46 percent to C$57.35. The Toronto Stock Exchange's S&P/TSX composite index fell 48.13 points, or 0.38 percent, to 12,551.61. Six of the index's 10 main sectors were in negative territory. "The markets have come out of the gates pretty good this year and I think investors are having a really hard time identifying where the new leadership is going to come from," said Newton. "I don't see anything starting to emerge as a strong trend yet. I don't want to get too optimistic." Copper prices eased from a one-week high amid uncertainty about the demand outlook for industrial metals. Diversified mining firm Teck Resources Ltd was the biggest drag, retreating 2.49 percent to C$36.79. The overall materials group, home to mining firms, was down 0.7 percent. Gold miners tracked bullion prices that fell following its biggest one-day rise this year. Barrick Gold Corp pared earlier losses and was trading down 0.68 percent to C$33.72 mid morning. Energy stocks were also off 0.44 percent, with Suncor Energy off 0.54 percent to C$33.40. Oil prices eased on growing concern that demand for the commodity could be softening amid a lackluster global economic environment. A Bank of Montreal downgrade to "underperform" of Blackberry maker Research In Motion Ltd failed to worry investors, with shares up 0.76 percent to C$11.88 after edging lower earlier in the session. "What's really interesting about that downgrade is that RIM is holding up not too badly," said Newton.