U.S. stock indexes closed mixed Friday, responding to a global downturn and jolted by a $2 billion loss announced by investment bank JPMorgan & Chase. The blunder shook up financial stocks and JPMorgan shares fell 9.28 percent to close at $36.96. The Dow Jones industrial average lost 34.44 points or 0.27 percent, to 12,820.60. The Nasdaq composite index picked up 0.18 point or 0.01 percent to 2,933.82. The Standard & Poor\'s 500 index lost 4.60 points or 0.34 to 1,353.39. The listed volume on the New York Stock Exchange was 2.03 billion shares with 1,209 shares advancing and 1,828 declining. The benchmark 10-year treasury note gained 1/32 to yield 1.845 percent. The euro fell to $1.2916 from Thursday\'s $1.2936. Against the yen, the dollar rose to 79.94 yen from 79.93 yen. In Tokyo, the Nikkei 225 index dropped 0.63 percent, 56.34, to 8,953.31. In London, the FTSE 100 index added 0.57 percent, 31.57, to 5,575.52.