See-Through Frogs Don't Negate Dissection

Some Japanese researchers have engineered frogs with transparent skin, so organs, blood vessels, or even tumors can be observed without performing a dissection.

"You can watch organs of the same frog over its entire life as you don't have to dissect it. The researcher can also observe how toxins affect bones, livers and other organs at lower costs," he told AFP.

The frogs are rare mutants of the Japanese brown frog (Rena japonica), which have been crossed to contain two sets of recessive genes. The mutants are fertile, as are their offspring, but the grandchildren die shortly after birth. A search on Pubmed suggests that the work has not been published yet, or is in press, so I am not sure as to exactly how the frogs were created or the genes involved.

The mainstream news has touted this discovery along the lines of 'dissections no longer needed!' However one look at the frog shows that this would not be the case. Unlike zebrafish, which are relatively flat and completely transparent, these frogs are decidedly *not* flat and the skin is only translucent. This means that only the organs closest to the skin's surface can be detected, and the observations will only be of a very precursory kind.

The value of this model would be the ability to monitor tumor growths, or linking fluorescent proteins to toxins or tissues below the skin's surface, however you would still be unable to examine and track changes in many kinds of deeper tissues. Also, how can someone be able to realize the three-dimensional placement of organs by merely peering through the frog's semi-transparent skin? In addition, there is already a semi-transparent frog found naturally in nature, the glassfrog.