Link to the Current
Biology Summary. You can access the full pdf from here but you might need to be registered.
Also Science had this to say about the Talpid2 gene.
In normal chicks, shh was expressed in a region analogous to the sides of the gums, but in alligators and talpid2 mutants, shh appeared in the center of the gums. The mutant version of talpid2 thus appears to turn shh on in the right place for growing teeth. Over time, changes in the gene may have disrupted this ability, resulting in tooth loss, the researchers report 21 February in Current Biology.
Here's the link to the
Sciencearticle.
This message has been edited by DBlevins, 02-23-2006 05:51 PM