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Similar results reported in paddlefish

Posted by tabin on 20 Aug 2007 at 14:04 GMT

The results indicate that a second, distal phase of Hoxd gene expression is not uniquely associated with tetrapod digit development, but is more likely a plesiomorphic condition present the common ancestor of chondrichthyans and osteichthyans. We propose that a temporal extension, rather than de novo activation, of Hoxd expression in the distal part of the fin may have led to the

This is an important study revising the way we view the evolution of the autopod and the role of Hox genes in the fin-to-limb transition. The take-home lesson is given all the more credence by a conceptually similar analysis, that was published while this study was in preparation, that examined Hox expression in the fin buds of ray-finned fish (the paddlefish), and reached the same conclusion (Davis et al 2007).