Have scientists demonstrated an absent protein can cause chicks to be born with scales rather than feathers (as well as reptile scales to feathers)?

Question

While researching and educating myself about evolution, I've come across an interesting claim that I'd like to learn more about, but so far, I've only been able to find the claim and no sources or evidence. For example consider following:

• Scientists blocked the production of one protein in chicken eggs, and the chicks were born with scales rather than feathers. - Information Theory and Intelligent Design Can Information Increase in a Biological System

• A single point mutation turns feathers back into scales in chickens -Feathers, Fables, Dinosaurs and Ham

Now I did find another claim which provided a source, but it appears to be saying something different (the opposite in away), and the sited link (Poling, J. 1996. Feathers, scutes and the origin of birds. Dinosauria on-line. Retrieved April 11, 2007) is broken:

Experiments show that the same protein (when missing before birth) that causes bird feet to stay webbed, causes bird scutes and scales to become feathers (Poling 1996) - New World Encylcopedia

I'm aware that the debate on the origin of feathers (and flight) is ongoing among scientists with several hypotheses being proposed, as very well described in a recent National Geographic article from Feb 2011. While I am interested in this in general, I'm currently trying to make sense of the claims mentioned above. Can they be substantiated, or are they baseless? I've spent about an hour searching online and haven't found anything but ambiguity (which scientists, which protein/mutation, etc).

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Update

I also found this related claim at evolutionwiki.org, emphasis mine:

Scientists have actually discovered that the same protein (when missing at birth) that keeps bird feet webbed causes reptile scales to become feathers. Birds thus could be descended from any number of reptilian species, also clear and powerful evidence for the evolution of birds from reptiles.

This claim here seems to be a variation of the one above, but with reptile being used instead of bird. It is for reasons like this, and for lack of references, that I am very skeptical of these claims. They give the impression that a key gene mutation that stops the production of a protein will cause chicks to be born without feathers and instead contain scales. Or that again, a key gene mutation that stops the production of a protein will cause a developing reptile to be born with feathers instead of scales. This later claim seems even more extraordinary if you ask me.

Answer 1

This is not an exhaustive or conclusive answer, but I've come across experiments that show the following:

• In a paper from 1980, Danielle Dhouailly, Margareth Hardy, and Philippe Sengel succeeded in introducing retinoic acid (Vitamin A) to induce feathers instead of scales to form on chicken feet
• Matthew Harris and John Falon were able to cause feathers on Silkie Birds to form on legs instead of scales by "turning-on" one of two feather genes before scales form (as mentioned in a recent Discovery Channel video)
• An article written by Leah Lefler over at HubPages.com mentions that the work of Harris and Fallon mentioned above can be reversed to turn feathered areas into scales as well.
• Around the 1950-1970s Danielle Dhouaillly, Philippe Sengel, and others performed experiments that show it's possible to graph lizard epidermis over chick dermis, and feather-bud sized appendages appear in a hexagonal feather pattern (see figure 12 in the article, which is also linked at the end of this answer). Additionally, Lizard epidermis grafted over chick dermis can develop into scales having a large size, shape and distribution similar to those of bird scales (see figure 11).

Conclusion:

The references show that the scales on the feet of some birds can develop feathers instead, and that some areas where feathers normally are can have scales instead (though this later claim I'm not sure is substantiated enough, at least in the reference sited - Leah Lefler's article).

Either way, it seems to me that the claims shown in the question have a measure of truth to them, some more so than others, but are very simplified claims, likely even containing errors, that could cause a person to draw distorted conclusions. For example, the research certainly doesn't show that a baby lizard can be born today with feathers instead of scales.

Recombinant lizard/chick experiments http://htmlimg1.scribdassets.com/6v5wbrwp4w1jbq4k/images/8-a6811b38ed.jpg