US STOCKS-Wall St sells off on weak earnings, election fears
* All 11 S&P sectors close in negative territory
* Alcoa, Illumina plummet after disappointing reports
* Dollar's rise, oil's decline also weigh
* St. Jude falls after warning on battery flaw in heart device
* Indexes down: Dow 1.09 pct, S&P 1.24 pct, Nasdaq 1.54 pct (Updates with close of U.S. markets)
By Lewis Krauskopf
Oct 11 (Reuters) - Wall Street sold off on Tuesday as disappointing corporate reports gave a sour tone to the start of earnings season and investors digested possible changing dynamics for the upcoming U.S. elections.
Alcoa shares tumbled 11.4 percent after the metals company's quarterly profit missed estimates and it lowered its revenue forecast.
Illumina shares plummeted 24.8 percent and were among biggest drags on the S&P 500 after the diagnostic test maker's weak quarterly update. Continuación...