Japanese researchers breed transparent frogs

A transparent frog whose organs can be seen through its skins is seen at a laboratory of Hiroshima University's Institute for Amphibian Biology in Hiroshima, western Japan, in this photograph released by the institute September 25, 2007.

TOKYO (Reuters Life!) - Japanese scientists have bred transparent frogs, whose internal organs can be seen through their skins, giving researchers who study diseases such as cancer insight into organ growth and development.

The frogs are the first of their kind, said Professor Masayuki Sumida, who led the project at the Institute for Amphibian Biology at Hiroshima University.

"In the past, there haven't been any reports on transparent four-legged animals," he told Reuters.

The animals have been bred from common Japanese Brown Frogs gathered in frog hunts around the country. Since they don't dissect the amphibians, researchers can continue to use the same frogs to observe changes in organ mechanisms or the effects of certain chemicals.

"Because the frogs remain transparent from their birth to adulthood, organs of the same frog could be studied throughout," Sumida said. "This is simple and cheap when studying, for instance, how certain chemicals influence bones."

By attaching green fluorescent protein to a stretch of DNA and injecting it into the frog, researchers can trace different genes from the outside as affected areas of the frog will glow.

The scientists plan to patent the see-through amphibians but they have not yet perfected the process.

Only one in 16 frogs they breed is transparent and they have not managed to maintain the transparency to a second generation.

"Their eggs develop poorly, so it's difficult to maintain them for many generations," Sumida said.