The genome of a primitive fish that was once thought to have died when the dinosaurs did has now been sequenced by scientists — and when put into mice, some of the fish DNA caused mice to sprout limbs. The new analysis, described today (April 17) in the journal Nature, could help to reveal how primitive fish swapped their fins for limbs when they moved from land to sea.
The fish, called a coelacanth, seems to carry snippets of DNA that can turn on genes that code for forelimbs and hind limbs in mice. The new discovery could shed light on how four-legged creatures, called tetrapods, evolved. "It really is a cornerstone from which we can view tetrapod evolution," said study co-author Chris Amemiya, a geneticist at the Benaroya Research Institute in Seattle, Wash.