With a genetic test, the text color of the gene traits change colors. Blue becomes purple and so on. Any idea why this happens?

Blue: visible trait
Green: carried trait (unknown until tested)
Purple: visible trait with another trait "hidden" underneath (unknown until tested)

It won't happen for every pet: some pets have, say 2v, and they have no carries or hiddens, so they'll just stay blue after testing. But if new traits pop up and things change colors, then the tester has revealed carries and hiddens on that pet.

Those traits can be passed down even if the pet hasn't been tested - they're still on the pet no matter what. But if you want to know what they are, testing is the only way to reveal them.

How do you know what the hidden trait is underneath the other visible trait? It doesn't come up with the genetic testing kit.

If you're not a weirdo like me who has many traits memorized for your favorite species
You can check the generator.

I put a couple in the generator, but all it shows is the visible trait so I still don't know what the second trait is.

https://www.sylestia.com/view/pets/?petid=4468193
https://www.sylestia.com/view/pets/?petid=4547807
https://www.sylestia.com/view/pets/?petid=4558871
https://www.sylestia.com/view/pets/?petid=4589050
https://www.sylestia.com/view/pets/?petid=4556167

A lot of my pets showed purple genes with testing so far.

Well, yeah, but you can look at the hidden letters and then scroll down the list of genes to find it.

So, like, the first one has AD in gene 3. Looking at the draes in the generator, I can easily find that G3D is Star Runes.

So the second letter in the gene letters is the hidden trait?

Yep.

I think I get how to read it now. Thanks.