Understanding GX

I see gorgeous Kenyan Sand Boas with the GX trait come across the marketplace every now and then. I haven’t been able to find anything about GX in sand boas while looking around the interweb other than pictures of them. 99% of the time I’ve seen them, they are listed as also possessing the paint gene. I have seen one example that was listed as a visual GX (het paint). This animal appeared to show a reduced pattern and a lighter base color (almost reminding me of a fainter canary dodoma).
I figured it time to hear from the experts. Could you help me in understanding the GX gene a bit better? What does it stand for? Is the way that I described typical of the way the gene presents itself visually? Is there a reason it is almost always found with the paint gene? Any additional knowledge is greatly appreciated!


I’ve also wondered about that trait.
@westridge should be able to clarify.

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GX is a recessive gene discovered by Jeff Holloway in his collection. It originated within a paint group, hence the reason it is usually accompanied by the paint gene. It is, however, a completely separate gene. GX simply stands for Gene X. The characteristics of GX are a significantly reduced pattern and clean head. This is a GX Paint we produced this year:

We also produced a couple of animals that may be GX Stripes, but we will have to test breed to confirm this, as the combo may not have been made yet.

Here is an animal produced by Rufus Daren that is an example of a GX that is not also a paint.


We produced a number of animals this year that look like this, but we are not 100% sure that they are visual GX, because the sire of the litter is also part Dodoma, which can create a similar appearance. The pairing that produced all of our GX and Paint stuff was from breeding a 25% Dodoma het GX Paint to a Stripe het GX Paint. For this reason, we are selling most of them as 66% possible hets, but it is highly likely that at least some of them are visual GX. Here are some pictures:

We think this one might be a GX Stripe:

So yeah, lots of test breeding to do. We also have a GX Paint Snow project going, but we won’t see babies from them for a few years.


Thank you so much for answering all my questions! Beautiful examples of your own there.

This was actually the exact animal I was referring to. I can’t wait to see how your project with the gene continues!

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This is a perfect example of why you are so important to us here @westridge :+1:

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I thought I’d post a comparison pic of what I think is a GX Stripe (right) and a normal Stripe sibling (left).


It really does look like when GX is paired with the stripe that it creates a much cleaner appearance. Thank you for the reference pics!

GX is an incredible gene that enhances any combo, a must have for any breeding collection of KSB.

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