Re: [pyrnet] Black Pyrenees, White Newf...

["Linda Weisser" <lmweisser@attbi.com>]

What we're discussing here is a white inheritance pattern called "extreme
piebald".  What it essentially means is that the animal is genetically a
colored animal with white spotting that has gotten so extensive that it
masks the color which is sometimes manifested in markings on ears and head,
base of tail and occasionally the body.  We are getting off track slightly
by talking about "black".  All that is meant is that the "base" of the dog
is colored (of whatever color) and not white.  Extreme piebald is an
identified and accepted form of inheritance in what appear to be white
animals.  Pyrs are identified as extreme piebald in Little's book The
Inheritance of Coat Color In Dogs which is, decades later, still considered
the "bible" of color inheritance.  Now, there has been some debate over the
identification of Pyrs with this inheritance pattern.  That is a legitimate
debate but no "better" explanation has been put forward.  The possibility of
being extreme piebald may help to explain why deafness is so rare in Pyrs
but isn't rare in many other white breeds.

Albino is, as has been pointed out, not part of this discussion.  True
albinos have a whole complex of characteristics which go way beyond just
being white.  Those things are not seen in Pyrs.

Linda