* Amazon jumps to record high after posting unexpected profit
* Visa rises after results beat expectations
* Biogen slumps after slashing forecast
* Dow down 0.09 pct, S&P down 0.12 pct, Nasdaq up 0.16 pct (Updates to open)
By Tanya Agrawal
July 24 (Reuters) - The S&P 500 and Dow Jones industrial average were lower on Friday while the Nasdaq composite gained amid a mixed bag of earnings from big companies and the downward spiral of commodities.
Metal prices hit multi-year lows as weaker-than-expected data from China and the euro zone raised concerns about global growth while oil prices neared four-month lows.
The three major indexes were poised to end the week in the red after disappointing corporate results and forecasts added to concerns about the U.S. profit outlook.
Amazon.com shares jumped as much as 20.4 percent to a record high of $580.57, a day after the online retailer posted an unexpected quarterly profit.
Dow component Visa was up 6.3 percent at $76.29 after the credit and debit card company's results handsomely beat expectations.
Starbucks rose 3.4 percent to $58.47 after the world's biggest coffee chain reported a higher quarterly profit.
At 9:44 a.m. ET, the Dow Jones industrial average was down 16.4 points, or 0.09 percent, at 17,715.52; the S&P 500 was down 2.53 points, or 0.12 percent, at 2,099.62 and the Nasdaq composite was up 8.25 points, or 0.16 percent, at 5,154.66.
Seven of the 10 major S&P 500 indexes were lower with the health index's 1.35 percent fall leading the decliners as Biogen's 15.8 percent slump weighed on the index after the biotechnology company cut its 2015 forecast.
Second-quarter S&P 500 earnings have been mixed, with 75 percent of companies so far beating analysts' profit expectations but just 52 percent surpassing revenue expectations, according to Thomson Reuters data.
RBC Capital Markets said investors were treating disappointing stocks harshly. While only 20 percent of companies have missed expectations, below the 23 percent over the past three years, there was a 3.5 percent selloff versus the 2.4 percent seen historically, a note said.
Adding to the concerns regarding lukewarm earnings, the S&P 500 is relatively expensive, trading at 16.9 times forward 12 months' earnings, above the 10-year median of 14.7 times, according to StarMine data.
"We still need to see more earnings to get some clarity on how this earnings season is going to turn out," said Adam Sarhan, chief executive of Sarhan Capital in New York.
"Investors are concerned about a lack of revenue growth and with the transport index being in correction territory and commodities selling off, there is a concern that the global economy isn't strong enough."
Investors will continue to focus on earnings report with nearly half of the S&P 500 companies having reported results.
American Airlines rose 2.1 percent to $41.67 after the company's quarterly profit beat estimates.
Data expected of Friday includes new single-family home sales for June, which is likely to remain steady at 0.546 million units. The data is expected at 10 a.m. ET (1400 GMT).
Declining issues outnumbered advancers on the NYSE by 1,739 to 910. On the Nasdaq, 1,399 issues fell and 904 advanced.
The S&P 500 index showed 10 new 52-week highs and 23 new lows, while the Nasdaq recorded 24 new highs and 82 new lows. (Editing by Don Sebastian)