Christine -
 
        White animals of several species - icluding ferrets, cats, some
Dalmatians, and several others often have congenital deafness.  Have you
ever heard that many blue-eyed white cats are deaf?  The ones that have
only one blue eye are often deaf on that side.
 
        There appears to be a connection between the lack of pigment and
lack of hearing - cells that produce pigment and cells that function to
conduct audio impulses in the ear are derived from the same embryological
source.  The lack of differentiation or migration in the developing fetus
affects both areas, so there is no pigment (especially in the eyes, which are
blue) and deafness.
 
        I know your ferret is not blue-eyed, but there are all types of
variations with these types of syndromes concerning severity of deafness, lack
of pigmentation, etc.  He may not be totally deaf, but hard of hearing instead.
 
        Best of luck
 
Bruce Williams, DVM
[Posted in FML issue 1135]