It is a common misconception that a dog with a merle coat must have hearing and seeing issues. The only time the merle gene causes a concern for health is when a dog is homozygous for merle, meaning “double merle.” The only way to get a homozygeous merle dog is to breed two merles together. This is something NO responsible breeder will ever do, including us!
A merle puppy out of Oregon Bordoodles has the same rare chance of being blind or deaf as any other puppy born with a normal genetic make-up. If you breed long enough, you are bound to have a statistical outcome of a puppy born with defects. I am blessed to say we have not yet had a single special needs puppy born here! I have many merle dogs now out in the world that were born here, into my hands. No owner has ever reported any heath concerns.
There are many, many well written research articles on the subject–but if you do a quick search to Wikipedia, at the top of page you will see it explaining the genetics further–and assuring the reader that only a homozygous dog is at risk and that a dog with a single merle gene has no greater risk than any other dog. :) Proudly breeding healthy merles here at Oregon Bordoodles!