What Is ALX4?
ALX4 is a gene associated with blue eye color in dogs. Researchers identified a duplication near the ALX4 gene that is strongly associated with blue eyes and heterochromia, including in some non-merle dogs.
Dogs with one or more copies of the duplication are more likely to have blue or partially blue eyes, but it is not a guarantee. Some carriers may have one blue eye, two blue eyes, partial blue coloring, or even two brown eyes while still being able to pass the duplication to their offspring.
Why ALX4 Matters to Our Program
At O’Hearon’s Amazing Puppies, ALX4 is only one part of the bigger picture. We are interested in the possibility of blue or partially blue eyes, especially in traditional tri and non-merle Bernedoodles, but appearance is never our only priority.
Every pairing is considered with health, temperament, structure, coat quality, genetic diversity, and overall compatibility in mind. Our goal is to thoughtfully incorporate ALX4 into future generations while continuing to produce well-rounded Bernedoodles that make exceptional family companions.
What ALX4 Can — and Cannot — Tell Us
ALX4 can increase the likelihood of blue or partially blue eyes, but it does not guarantee them. Eye color can vary even within the same litter, and some dogs may carry the duplication without visibly having blue eyes. ALX4 also does not determine overall coat color, temperament, structure, health, or quality.
ALX4 is separate from the merle gene. A dog carrying the ALX4 blue-eye-associated duplication can be paired with a merle-colored dog when the rest of the genetics are appropriate. Merle itself still needs to be managed responsibly, because breeding two merle dogs together can create double-merle puppies and associated health risks.
Hank does not carry merle, which gives us flexibility to consider both merle and non-merle females in future pairings while still managing the merle gene responsibly.
Looking Ahead
ALX4 is part of our long-term vision for thoughtfully planned Bernedoodle pairings, including future traditional tri, non-merle blue-eye possibilities, and other carefully selected combinations as our program develops.
As we move forward, health, temperament, structure, coat quality, and responsible genetic planning will always come first. ALX4 is one exciting piece of the picture — not the whole picture.