NEW YORK, Nov 26 (Reuters) - News of a coronavirus variant potentially resistant to current vaccines sent investors dashing for the safety of the Japanese yen and the Swiss franc on Friday, while traders also took profits after an extended rally in the U.S. dollar. The yen and franc gains came at the expense of the growth-sensitive Australian dollar and Norwegian crown though thinner volumes after Thursday"s U.S. Thanksgiving holiday made market moves more volatile. Little is known of the variant first detected in South Africa, but scientists say it has an unusual combination of mutations that could make it able to evade immune responses and be more transmissible. read more "It almost feels like the initial working assumption for most market participants is that this is a new phase of the pandemic, new lockdowns and restrictions will maybe be put in place, and it certainly feels like we"re going to need a new vaccine as well," said Bipan Rai, North American head of FX strategy at CIBC Capital Markets in Toronto. One of the main gainers was the yen, which bounced off five-year lows hit this week against the greenback, and jumped more than 1% to a high of 113.66. The currency was on track for its best day since March 2020. The euro rose 0.75% to a high of $1.1297 , though it fell to more than 6-year lows against the resurgent Swiss franc at 1.04335 francs per euro. "This is a textbook flight to quality into yen and the Swiss franc on the new virus strain with the thin liquidity also a factor which may accelerate the unwinding of short bond positions," Kenneth Broux, a strategist at Societe Generale in London, said. Speculative accounts had been massively short safe-haven assets, with U.S. CFTC figures showing net bearish positioning at $1.2 billion and $10.3 billion for the yen and Swiss franc respectively in the latest week. The dollar index dipped 0.56% to 96.218, after reaching a 16-month high of 96.938 on Wednesday. It has jumped from 93.872 on Nov. 9 as investors increased bets that the Federal Reserve will begin raising rates in mid-2022 to thwart stubbornly high inflation. CIBC’s Rai said Friday"s decline in the greenback was more likely due to investors taking profits after the currency’s recent gains, and not a change in dollar’s safe haven status. "The near-term move is mostly about extended positioning and closing those out, once that becomes a little bit more finely balanced and if we are in a risk-off scenario then I would expect the dollar to continue to outperform," he said. Sterling briefly slipped to a new 2021 low below $1.3278 as the jitters prompted some to scale back bets on an interest rate hike in December. read more