LONDON (Reuters) - With the 11th Doctor Who quitting the Tardis, fans of the popular sci-fi television series are debating whether it is time for a woman to step into the well-travelled shoes.

Matt Smith's decision to quit the popular BBC TV series after a 50th anniversary show in November and a Christmas special has sparked speculation of a 21st century makeover for the doctor, who has battled Daleks and Cyberman since 1963.

Bookmaker William Hill was offering odds of 8-1 on the next Dr. Who being a woman with suggested actresses including Billie Piper, who played the doctor's sidekick Rose Tyler a few years ago, Tilda Swinton and Olivia Colman.

Ladbrokes was offering odds of 20-1 on Helen Mirren taking the role in the series that is broadcast in up to 48 countries with 77 million viewers in Britain, the United States and Australia alone.

An editorial in Britain's Times newspaper joined the debate, saying Dr. Who started as an attempt to teach viewers about history and has always been closely connected to big events.

"The shift from male to female authority is difficult in politics and business but it is sDrurely not beyond the capacity of the Doctor," wrote the Times in an editorial.

Some fans, however, were adamant that a man should fill the role held by William Hartnell, Patrick Troughton, Jon Pertwee, Tom Baker, Peter Davison, Colin Baker, Sylvester McCoy, Paul McGann, Christopher Eccleston and David Tennant.

"Are BBC intent on sacrificing all remaining Dr Who fans on the altar of political-correctness?" tweeted one fan.

But the chance of a female Dr. Who remained a long shot.

William Hill had its joint favorite replacements at 10-1 as Rupert Grint of Harry Potter fame and Russell Tovey who appeared in a couple of Dr. Who episodes.

Ladbrokes' favorite at 3-1 was Rory Kinnear, son of Roy Kinnear, who is a recurring player in the James Bond series.

The show's lead writer and executive producer, Steven Moffat, was giving nothing away.

"Somewhere out there right now, all unknowing, just going about their business, is someone who's about to become the Doctor," he said in a statement announcing Smith's departure.