Last checked at 
(Adds close of U.S. markets)
* Silver prices rise on social media speculation
* J&J falls as vaccine disappoints
* Bitcoin jumps 14% after Elon Musk mention
* Treasury yields rise after inflation data
By Herbert Lash and Carolyn Cohn
NEW YORK/LONDON, Jan 29 (Reuters) - Silver prices jumped and
global equity markets sank on Friday amid a growing battle on
Wall Street between hedge funds and retail investors, while a
dispute over COVID-19 vaccine supply in Europe cooled risk
appetite.
Disappointing vaccine data from Johnson & Johnson
also hurt sentiment but the assault of retail traders using
online forums to force hedge funds to reverse short positions -
bets that stocks will fall - kept the market on edge.
Shares of GameStop Corp and AMC Entertainment
Holdings Inc surged again after Robinhood and
Interactive Brokers said they planned to ease restrictions after
imposing buying halts on Thursday.
GameStop soared 67.9% to $325 a share, five times its
closing price a week ago Friday, and AMC gained 53.7%, both in
heavy trade. AMC was one of the most active stocks on the New
York Stock Exchange. Volume on U.S. exchanges was 16.83 billion
shares, up from the 10.6 billion average in the fourth quarter.
Silver rallied and was up 2% at $26.90 an ounce,
taking gains to almost 10% since messages began to circulate on
Reddit early Thursday urging retail investors to pile into the
market and drive up prices.
Anxiety has grown as investors ask whether hedge funds will
need to liquidate other positions to address losses in stocks
they have shorted, said Michael Arone, chief investment
strategist at State Street Global Advisors in Boston.
"Once this short squeeze inevitably ends and there aren't
any more greater fools to bid up these stocks, will retail
investors get stuck holding the bag?" Arone asked.
"The unintended consequences of this potential volatility
have markets on edge as we end the week," Arone said.
Arone added that investors need to take a giant step back as
earnings are strong, the economy is improving, fiscal and
monetary policy is supportive and vaccines are rolling out.
MSCI's benchmark for global equity markets
fell 1.82% to 642.57, while Europe's broad FTSEurofirst 300
index closed down 1.95% at 1,524.1 to post its worst
weekly loss, at 3.3%, since October.
On Wall Street, the Dow Jones Industrial Average fell
2.03%, the S&P 500 lost 1.93% and the Nasdaq Composite
dropped 2%. The three indexes suffered their biggest
weekly fall since the end of October.
MSCI's broadest index of Asia-Pacific shares outside Japan
fell 1.1% to post a weekly loss of 4.4%. Japan's
Nikkei fell 1.9%, recording its first weekly loss of the
year.
VACCINE DISPUTE
Delays in COVID-19 vaccine production have snowballed into a
spat between Britain, the European Union and drugmakers over how
best to direct limited supplies.
AstraZeneca Plc offered eight million more doses of
its COVID-19 vaccine to the European Union after it unexpectedly
announced supply cuts last week. But the bloc said that was far
short of what was originally promised, an EU official told
Reuters on Friday.
New variants of the novel coronavirus have prolonged
lockdowns and delayed expectations of an economic rebound.
Click here http://tmsnrt.rs/2EmTD6j for an interactive chart
on the vaccine race.
The U.S. dollar retreated from its highest level since
mid-November against the Japanese yen as investors
rebalanced portfolios for month-end. The greenback slid 0.48%
against the yen and traded little changed against an index of
currencies, falling 0.002%.
Bitcoin jumped as much as 14% to a two-week high
after Tesla Inc chief Elon Musk tagged the
cryptocurrency in his Twitter biography.
French 10-year government bond yields, which
move inversely to price, rose four basis points after France's
gross domestic product contracted less than expected in the
fourth quarter of 2020.
U.S. Treasury yields rose, in line with those in Europe,
after data showed inflation perked up last month, while
employment costs rose, suggesting the world's largest economy is
on the mend from the devastating effects of the pandemic.
The U.S. yield curve steepened as long yields increased,
with the spread between 2-year and 10-year notes hitting 98.20
basis points, the widest in about a week.
The 10-year U.S. Treasury note rose 2.1 basis
points to yield 1.0757%.
Oil prices traded mixed as demand concerns caused by new
coronavirus variants and slow vaccine rollouts offset a cut in
Saudi Arabian oil supply and falling U.S. oil inventories.
Brent crude futures settled up 35 cents at $55.88 a
barrel. U.S. crude futures fell 14 cents to settle at
$52.20 a barrel.
Spot gold prices rose 0.16% to $1,843.31 an ounce.
U.S. gold futures settled up 0.5% to $1,850.30 an ounce.
(Additional reporting by Tom Westbrook in Singapore and Alwyn
Scott in New York; Editing by Will Dunham, Richard Pullin, Ana
Nicolaci da Costa, William Maclean, Larry King, Dan Grebler and
Richard Chang)
