LONDON/HONG KONG—World shares gained on Tuesday as investors weighed up the extent to which the Omicron coronavirus variant would hit economies around the world, with the dollar softening as appetite for riskier assets made a cautious return. The broader Euro STOXX 600 rose as much as 1.1 percent. German DAX’s added 0.8 percent, with London’s FTSE climbing 0.9 percent. Semiconductor and chip stocks grabbed the limelight, with ASML Holding, ASM International, and STMicroelectronics all up around 2 percent after a positive trading update from U.S. chipmaker Micron Technology. “It’s a game of trying to assess to what extent the Omicron story is going to cause uncertainty,” said Olivier Marciot, senior portfolio manager at Unigestion. “Even though it’s going to be impactful for real life and the real economy for a few weeks, markets are hoping it won’t lead to what everyone fears, which is a global slowdown.” The MSCI world …