* Dow, S&P 500 coming off record closing highs
* Volume likely to be light in holiday week
* Crude oil rises, could support energy shares
* Futures down: Dow 40 pts, S&P 3.5 pts, Nasdaq 3.25 pts (Updates prices, adds biotech stocks)
By Ryan Vlastelica
NEW YORK, Dec 29 (Reuters) - U.S. stock index futures were slightly lower on Monday, as investors found few reasons to keep pushing shares higher following a sharp rally that has taken major indexes to repeated records.
The Dow has risen for seven straight sessions, the longest streak for the blue-chip index since March 2013, while the S&P 500 is up 5.9 percent over the past seven sessions, ending at its 52nd record close of the year on Friday.
The speed and scale of the rally could make further gains difficult to come by, especially in the final trading week of the year, when many market participants are out on holiday and there are few trading catalysts. Trading volume is expected to remain light, which could leave the market more susceptible to big swings.
Biotech stocks were among the biggest movers of the premarket session. Gilead Sciences rose 2.1 percent to $95.75 before the bell after Morgan Stanley upgraded the stock to "overweight" from "equal-weight." Juno Therapeutics rose 7.5 percent to $52.37 after the company, in an 8-K filing, authorized a stock buyback program of 495 million shares.
Energy shares will continue to be in focus as crude oil rose 1.3 percent to $55.41 on concerns about disruption to exports from Libya. Oil has dropped in 12 of the past 13 weeks, weighing on the S&P energy index, which is by far the weakest sector of the year, down 9 percent.
Indexes are on track to close out a third straight positive month. Thus far in December, the Dow is up 1.3 percent, the S&P is up 1 percent and the Nasdaq is up 0.3 percent. In the fourth quarter, the Dow is up 5.9 percent, the S&P is up 5.9 percent and the Nasdaq is up 7 percent. Both the S&P and Nasdaq are on track for their eighth straight quarterly gain, the longest for the S&P since 1998 and the longest for the Nasdaq since 1996.
In 2014, the Dow is up 8.9 percent in its sixth straight yearly gain, the S&P is up 13 percent and the Nasdaq is up 15 percent. Recent gains this year were fueled by strong economic data, including a bullish read on economic growth last week, as well as accommodative measures from central banks.
Futures snapshot at 7:32:
* S&P 500 e-minis were down 3.5 points, or 0.17 percent, with 77,779 contracts changing hands.
* Nasdaq 100 e-minis were down 3.25 points, or 0.08 percent, in volume of 13,784 contracts.
* Dow e-minis were down 40 points, or 0.22 percent, with 15,488 contracts changing hands. (Editing by W Simon)