Ever wonder why some Pugs are black and others are fawn? I did, and that’s why I did some research on the topic. I don’t know why I didn’t figure this out since I got an "A" in high school Biology, I must have forgotten that class.
But it’s all about genes passed down from parent to offspring. Don’t worry there won’t be a test here and there won’t be any crazy terms here either. Except for chromosome, which I really want to use. I guess my Biology teacher Mr. Hutton was right when he told me 20 years ago that someday I’d use the word "chromosome" after I asked him why I had to learn this since I’d never, ever use it. Anyway, genes come in pairs and reside on a chromosome it calls home, and it has its very own address.
Each member of a pair of genes can have a different form. With Black or Fawn coats in Pugs, one can call for the Pugs coat to be black, and one can call for it to be Fawn with the black markings around the face and ears. But no matter which call the genes make, the black one makes the decision if it has any say in the matter and because of that it is called the dominant gene.
If in this gene pair both members call for black, the Pug will be black. If in this pair one member calls for black and the other for fawn, the Pug will still be black because the black one rules. The only way for a Pug to be fawn is if both members of the gene pair call for Fawn.
Simple huh? And I didn’t even have to use any of those icky Biology terms!
Photo of Squiq submitted by pug forum member Pinkles.