Two hair samples came up trumps -- one from a beast shot in the Kashmiri region of Ladakh 40 years ago and the other found in Bhutan a decade ago.
"In the Himalayas, I found the usual sorts of bears and other creatures amongst the collection," Sykes told BBC radio, ahead of the broadcast of a TV programme about his findings.
"But the particularly interesting ones are the ones whose genetic fingerprints are linked not to the brown bears or any other modern bears, (but) to an ancient polar bear."
The DNA from the Himalayan samples was a 100 percent match with a sample from a polar bear jawbone found in Svalbard in Norway, dating back between 40,000 and 120,000 years.
Brown bears and polar bears are closely related as species and are known to interbreed when their territories overlap, according to Sykes.
"This is an exciting and completely unexpected result that gave us all a surprise," he said in a statement, adding: "There's more work to be done on interpreting the results.
"I don't think it means there are ancient polar bears wandering around the Himalayas. But... it could mean there is a sub-species of brown bear in the High Himalayas descended from the bear that was the ancestor of the polar bear.