This is an interesting subject for me, because when I first started breeding and selling online in 99, I had what I believe to be a circle back and it seemed/seems it was genetic, possibly even a dominant gene. You could see a faint circle on her back, and most of her babies came out circleback. I have kept in touch with the owner of one of her offspring circlebacks and he told me that all of that one's babies came out circleback as well. I don't know what his male was/is.
As cool as that sounds, they rarely (if ever) keep the circle into adulthood. So, you're probably right, unless you like them only for their baby patterns, their time has probably come and gone.
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Rob Jenkins
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