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The Facts of Blue
Eyed Tri's
Phantom
Merles
The facts of Blue Eyed
Tri's
Many breeders believe
that the blue eyed tri is an inherited gene that can be passed along
to their offspring, thus making blue eyed tri puppies more
valuable. Many breeders and potential breeders pay excessive
amounts for blue eyed tri puppies with the belief that they will
produce blue eyed tri's. It appears from the article that many
factors are involved in the creation of the blue eyed tri, so one
combination of male and female may produce the blue eyed tri, and
another combination may not. It is up to the individual
breeder to decide whether or not to invest additional money in a dog
that may very well not produce blue eyed tris unless combined with
another dog with just the right gene pool. It is also up to
breeders to refrain from advertising the "blue eyed tri gene", as it
apparently does not exist.
The following
information is taken from an article by the Australian Shepherd
Health & Genetic Institute. You can find the entire
article at www.ashgi.org/articles/fact_blue_eyed_blacks.htm
"Sometimes Australian
Shepherds which are not merle will have blue eyes. Thse eyes
(sometimes one, sometimes both) are completely blue, or perhaps half
blue/half pigmented. They are never flecked or
marbled.
This kind of blue eye
has nothing to do with the merle gene, white trim genes or the
albino gene. These eyes are completely
sound.
The
mode of inheritance is UNKNOWN, but since the blue eyes can be
single or a pair and an individual eye may be half-and-half, there
is probably more than one gene involved."
Phantom Merles
Sometimes
breeders combine a merle with a tri and the result are homozygous
merle puppies.(lethal whites) Since everything was done
correctly, this would appear to be impossible. The cause of
this irregularity is the phantom
merle.
The following
information is taken from an article by the Australian Shepherd
Health & Genetic Institute. You can find the entire
article at www.ashgi.org/articles/fact_phantom_merle.htm
"Phantom merles, more properly called cryptic
merles, are dogs which carry a merle gene but are phenotypically
(look like) tri or bi. Most such dogs will have some small
area of merleing somewhere. One of the most famous in this
breed, Fieldmaster of Flintridge, looked like a black tri except for
one or two very small merle areas. Theoretically it is
possible that a dog would have no merling and be a cryptic merle,
but this would be extremely unusual. Sometimes the only merle
spot will be on the tail which is docked in Australian
Shepherds.
Cryptic merles should be registered as merles
because they will breed like merles. If
bred to a non-merle, merle puppies will be produced. If bred to another merle, homozygous merle
puppies will probably be produced. Merle offspring of a
cryptic merle will virtually always be "regular" merles, not cryptic
merles.
Excessive white markings in puppies from a
tri-to-merle cross are not "proof" that the tri parent is a "phantom
merle." Excessive white markings in such a cross are the
result of genes which code for white trim and have nothing to do
with merle." | 
