Are there really any CoDomiant Morphs in Leopard Geckos?

First of all, it's very difficult to compare cornsnake genetics with that of leopard geckos. I have found that with leos, it is not as straight-forward as with corns, and there seems to be more questions raised with every question answered.

I think where many are confused is when we refer to a 'het' simply in terms of recessive traits. "Technically", the term heterozygous means that each offspring carries one copy of each parent's genetic make up, and in some cases it's the copy copy that isn't expressed. So, when we look at Mack Snows as co-dominant, we see that with a Mack Snow x Normal, the offspring will either be a Mack Snow or it will not be. We rarely think that the Mack 'sibling' could be a het for Snow, but in reality it is heterozygous for snow.

To complicate things a little bit, Albey crossed his Linebred/Fasciolatus with Macks (not sure if they were Homo or Hetero for the Mack Gene), and to my knowledge no Super Snows were produced. I picked one of the offspring up, when she is ready to breed, I will be breeding her to my Tremper Hybino Male. I'll post my results from the cross once I have offspring to help prove anything out.

In this case if a Mack Snow was crossed with an E. fasciolatus, the offspring would either be macks or they would not be. The only way to produce SS's from that combination would be if both parents were snows. There have been SS's produced from Mack co-doms paired with line-bred snows.

Originally Posted by Golden Gate Geckos

So, when we look at Mack Snows as co-dominant, we see that with a Mack Snow x Normal, the offspring will either be a Mack Snow or it will not be. We rarely think that the Mack 'sibling' could be a het for Snow, but in reality it is heterozygous for snow.

What?

Mack Snow = Xx (het)
Super Snow = XX (homo)

So if a Normal is produced from Mack x Normal, it would not carry a gene for Mack at all, if in fact we're talking about co-dominance. A Mack Snow (if we're speaking of co-dominance) is the heterozygous while the Super Snow is the homozygous.

Originally Posted by Golden Gate Geckos

I think where many are confused is when we refer to a 'het' simply in terms of recessive traits. "Technically", the term heterozygous means that each offspring carries one copy of each parent's genetic make up, and in some cases it's the copy copy that isn't expressed. So, when we look at Mack Snows as co-dominant, we see that with a Mack Snow x Normal, the offspring will either be a Mack Snow or it will not be. We rarely think that the Mack 'sibling' could be a het for Snow, but in reality it is heterozygous for snow.

I totally agree with you on the definition of the word heterozygous Marcia, but I do not agree that a mack "sibling" (aka, normal offspring with a mack snow parent) is het for Mack Snow. Mack snows are the "het" for the mack snow gene, Super Snows are the "homo" for the Mack Snow gene. Mack snow is a dominant gene which has a super form, which makes it Co-Dominant. There is no het for Mack Snow just like there is no het for the Enigma gene. A Mack Snow carries only 1 copy of the Mack Snow gene, the mack "sibling" is created because the non Mack Snow gene got passed on to the offspring.