By Wayne Cole
SYDNEY (Reuters) - Global share markets shed early gains and sterling tumbled in Asia on Friday as early results from the UK's vote on European Union membership proved unnervingly close, sparking a wave of profit-taking across risk assets.
Sterling collapsed to $1.4475 , having earlier stretched to a high for the year at $1.5022 . The euro turned tail to hit $1.1324 and the yen recouped early losses to stand at 104.90 per dollar.
Futures for Japan's Nikkei shed 1.1 percent from its U.S. close, and EMINI futures for the S&P 500 were down 0.4 percent, having climbed 1.76 percent on Thursday.
Financial markets have been racked for months by worries about what Brexit, or a British exit from the European Union, would mean for Europe's stability.
Early opinion polls had favoured the "Remain" camp. An Ipsos MORI poll put the lead at 8 points while a YouGov poll found 52 percent of respondents said they voted to remain in the EU while 48 percent voted to leave.
Yet a trickle of official results showed the margins were nail-bitingly tight. Traders were particularly spooked by returns from Sunderland showing a large majority for the "Leave" camp and just a narrow win for "Remain" in Newcastle.
Safe-haven bonds immediately came back into favour, with U.S. 10-year Treasury futures jumping 19 ticks.
Commodities likewise swung lower as a Brexit would be seen as a major threat to global growth. U.S. crude eased 29 cents to $49.83 a barrel in erratic trade.
(Editing by Lincoln Feast)