LOS ANGELES (REUTERS) - Alicia Vikander won the best supporting actress Oscar on Sunday (Monday Feb 29, Singapore time) for her portrayal of the wife of a transgender artist in The Danish Girl.

It is the first Oscar for Swede Vikander, 27, who had a breakout year in 2015 with starring roles in Ex Machina and Testament Of Youth.

An emotional Vikander thanked her parents, The Danish Girl director Tom Hooper and co-star Eddie Redmayne.

"Eddie, thank you for being the best acting partner. You raised my game," she said.

Vikander was the youngest nominee in the category, beating far more experienced actresses including Kate Winslet, Rachel McAdams and Jennifer Jason Leigh. Rooney Mara, another rising star, rounded out the competition.

Vikander, whose mother is an actress, got her start acting on stage as a child in her native Sweden. She then trained as a ballet dancer for 10 years before being sidelined by injuries and turned back to acting.

Television and film roles followed, and she first received international attention for her 2012 role as Kitty in Anna Karenina.

Last month, Vikander won a Screen Actors Guild award and Critics Choice award for The Danish Girl, fuelling her momentum in the run-up to the Oscars.

The film tells the story of Danish artist Einar Wegener, played by Redmayne, who decides to live life as a woman named Lili Elbe. The film depicts the unusual love story between Lili and the wife who remained by her side, Vikander's Gerda Wegener.

The release of The Danish Girl capped a year when transgender issues went mainstream, fuelled by the success of award-winning TV series like Transparent and the transition of Caitlyn Jenner, the former US Olympic athlete.

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