April Fools’ Day has been around for centuries. While no one is totally clear on its origins, we all know it’s a day filled with practical jokes and hoaxes. Have you ever wondered if your dog is fooling you with their appearance?

We’ve run millions of DNA tests on dogs, and we often hear from owners that their shocked to find out that the pet they thought looked just like a Labrador, for example, in fact had no Lab in it. Looks can be quite deceiving. Visual breed identification, even when done by professionals, is only accurate about 25% of the time. So why is it that a dog’s physical appearance can so easily pull a fast one on us?

It has to do with their genetics. Physical appearance is only controlled by a very small portion of a dog’s genes. Dominant and recessive genes come into play as well. Dominant genes require only one copy in order for a trait to be seen/displayed/etc., whereas recessive genes require two.

Dominant traits, like short hair or a black coat color, can show up in hundreds of breeds, even though you may associate those traits with, say, a Labrador Retriever. Recessive traits, such as a brown or “chocolate” coat, may never make it past the dominant traits. So even though one copy of the gene is present, it will never be seen when you look at the dog.

For mixed breed dogs, the more breeds in the genetic history, the more diluted the characteristics in the genetic signature are likely to be. This can result in a wide range of shapes, sizes and color patterns in mixed breed dogs—and a lot of guessing when it comes to trying to visually identify their breed make-up!

Head over to the WisdomPanel.com for more info on how traits are inherited. And of course, to find out your dog’s breed make-up, consider one of our WISDOM PANEL™ dog DNA tests.