By YURI KAGEYAMA
AP Business Writer
TOKYO (AP) — Asian shares are trading mixed, as optimism set off by a rally on Wall Street was dampened by concerns about the potential impact of the omicron coronavirus variant. Benchmarks rose in Japan and South Korea, but fell in China. Markets were closed in Australia for a national holiday. Stocks made steady gains on Wall Street on Monday, enough to mark another record high for the S&P 500 index. Much is still uncertain about omicron, which is spreading quickly and prompting a return to pandemic restrictions in some places. Trading is expected to be quiet but potentially volatile this week as the omicron coronavirus variant continues to spread quickly throughout the U.S. and overseas.