* Futures: Dow up 15 pts, S&P up 2 pts, Nasdaq down 0.5 pts
By Abhiram Nandakumar
Dec 22 (Reuters) - U.S. stock index futures were little changed on Tuesday, ahead of third-quarter GDP data, even as crude oil prices edged up from multi-year lows.
* Brent crude looked set to make the first daily gains in five sessions as investors closed bearish positions ahead of Friday's Christmas holiday, but global oversupply concerns limited gains.
* Global stocks rose on Tuesday, lifted by the recovery in oil prices. U.S. stocks closed higher on Monday, helped by rallies in tech and hospital stocks.
* Trading volumes are expected to be relatively light this week, likely exacerbating volatility, with U.S. stock markets operating a shortened session on Thursday and closing on Friday for Christmas.
* The U.S. Commerce Department is expected to trim third-quarter GDP growth to an annual rate of 1.9 percent from 2.1 percent reported last month. The data is due at 8:30 a.m. ET (1330 GMT)
* U.S. existing home sales for November is expected to have remained steady, after falling 3.4 percent in October. The report is scheduled for release at 10:00 a.m.
* ConAgra Foods posts quarterly results before the bell, while Nike will report after the market closes.
* Dow component Nike's shares were up half a percent at $130.50 in premarket trading.
* Activision Blizzard was up 5.3 percent at $40.80 in thin volumes. The video game maker renewed its $250 million credit facility.
Futures snapshot at 6:44 a.m. ET:
* Dow e-minis were up 15 points, or 0.09 percent, with 21,936 contracts changing hands.
* S&P 500 e-minis were up 2 points, or 0.1 percent, with 121,355 contracts traded.
* Nasdaq 100 e-minis were down 0.5 points, or 0.01 percent, on volume of 19,546 contracts. (Reporting by Ankur Banerjee and Aastha Agnihotri in Bengaluru; Editing by Anil D'Silva)