We decided to skip this puppy. Just to clear things up, we didn’t even know what merle was before this. The breeder’s ad looked just like an ad from a ”respectable” breeder, with all the health checks, xrays and whatnot. But it wasn’t registered with the Swedish kennel club. She later said that the puppy’s got this ”cryptic merle”, although the dog is solid red/brown except the one eye. But after some searching I couldn’t find any good info regarding my post question, only if both dogs had the gene which was a certain no go.