Stock futures edge higher, on track for weekly gain

NEW YORK (Reuters) - U.S. stock index futures edged higher on Friday, putting major indexes on track for a second straight weekly advance, though moves were likely to be slight with few market catalysts and many traders extending their Christmas holiday.

* Wall Street has rallied of late, with both the Dow and S&P 500 touching intraday records in Wednesday's shortened session and the Dow eking out a sixth straight daily advance. The S&P 500 has risen 5.5 percent over the past six sessions and notched 51 record closes this year, the most since 1995 and the fourth best ever in terms of record closes.

* The gains have been sparked by central bank assurances about its intentions regarding interest rate policy and still strong economic data. While no major economic indicators were due Friday, the market's upward bias looked set to continue. Low volume could increase volatility.

* Market activity was quiet Friday morning, with one of the most actively traded names on the New York Stock Exchange, Peabody Energy Corp , trading only 3,100 shares by 7:12 a.m. EST (1212 GMT). The stock was flat at $7.71.

* U.S. crude futures rose 0.6 percent to $56.16 per barrel as unrest in Libya cut supplies, offsetting a growing glut in the United States and weak imports by Japan. The modest rise could help the beleaguered energy sector, which has fallen alongside commodity prices. Crude oil has fallen in 12 of the past 13 weeks.

* Biotechnology stocks will also be in focus following heavy volatility throughout the week. The Nasdaq Biotech index <.NBI> rose 1.6 percent on Wednesday in a partial rebound from the drop of nearly 7 percent over the previous two sessions.

* For the week, the Dow is up 1.3 percent, the S&P 500 is up 0.5 percent and the Nasdaq is up 0.2 percent. It is the second straight weekly gain for all three, and the ninth positive week in the past ten for the Dow and S&P.

Futures snapshot at 7:09:

* S&P 500 e-minis added 2.75 points, or 0.13 percent, with 7,792 contracts changing hands.

* Nasdaq 100 e-minis were up 11.25 points, or 0.26 percent, on volume of 2,112 contracts.

* Dow e-minis <1YMc1> gained 27 points, or 0.15 percent, with 2,131 contracts changing hands.

(Editing by Jeffrey Benkoe)