This goes into Neural Crest tissue and the normal ear. As we all
know by now, Neural Crest genetic variations such as KIT and perhaps
Waardenburg are why a range of problems from increased risk of
cardiomyopathy all the way to deafness or partial deafness occur in
ferrets w head blazes, panda white heads, and other extraneous white
spotting not found in standard ferret markings.

If the article is not available to nonsubscribers now it should be in
a week.  [login not required. BIG]  The actual topic is a different
flaw in how ears form but it describes clearly how the Neural Crest
is involved.

<http://www.sciencenews.org/view/generic/id/349161/description/How_mammals_grow_ears_With_a_flaw>

[Posted in FML 7739]