|
Chondrodysplasia is
a genetic disorder in which puppies are born with bone deformities, which may
become evident in abnormal shape and length of limbs as they grow. Also known
as "dwarfism," chondrodysplasia is caused by a simple recessive gene, which
means that both parents must carry this gene to produce an affected (chondrodysplastic)
puppy.
In very young
puppies (under six weeks of age), the deformity is usually impossible to detect
without x-rays, even to the practiced eye. Chondrodysplastic dogs (dwarfs) can
be affected in varying degrees. Some adults may appear almost normal, perhaps
just unusually small, while others may have a disturbing resemblance to a
Bassett hound. Chondrodysplastic malamutes can vary in size, just as
normal malamutes do. We know of "dwarf" malamutes who stand 26 or 27 inches at
the withers!
After it became
obvious in the 1970s that chondrodysplasia has a simple recessive pattern of
inheritance, a test-breeding program was implemented by the
AMCA to distinguish
carriers from non-carriers. While the program has been the source of occasional
controversy, there is no doubt that it has been highly effective in limiting
numbers of carriers of chondrodysplasia in the breeding population. The
AMCA
chondrodysplasia certification committee is still active today and has been
working with the Alaskan
Malamute Research Foundation to produce a
DNA test that will simplify the
task of identifying carriers and non-carriers.
|
