X2 I wish more people could understand this.......
It's nothing more complicated than a simple recessive gene...
Dogs don't need to be bred "tight", "inbred", or "linebred" to express a recessive gene.
Both dogs need to be carriers of the gene to express it in a litter of pups. Pink nose bred to pink nose will produce an all pink nose litter of pups.
I understand that it's a gene, just like glass eyes or leopard color, but if you only breed dog with pink noses your still doing a form of "tight" breeding. Thats what line breeding is keeping the gene or trait very close to try and repeat it. Most ppl do this based on ability but same goes for breeding for color and even if you do breed 2 pink nose dogs it doesnt mean the whole litter will be pink noses. I dont see any Rottweilers or Dobermans with pink noses. It has to be a gene mainly in the Ben bloodline somewhere.