From what I have read, that’s exactly right. Leucism and bug-eyes in rat snakes, including corns of course, are both tied to the MITF gene… as well as pied (same gene different loci is the hypothesis I think). I’m no geneticist so someone out there please correct me if I’m wrong, but doesn’t Het Palmetto resulting in any phenotypic expression, and the fact that a homozygous Palmetto does not produce all Palmetto young when bred to a normal, fit exactly with expectations for incomplete dominance? I know we sometimes see, or think we see “Het Markers”, associated with recessive genes, which makes no sense and complicates things, but what Palmetto does seems quite different to me.
I think @eaglereptiles needs to see this…
So are we in agreement that Palmetto is Incdom?
- Inc Dom
Democracy in action
The page names are incorrectly named. Palmetto is inc-dom, but a homozygous animal isn’t considered a super palmetto. Het palmetto and palmetto should still work fine (like het red axanthic and red axanthic in ball pythons). It’s what people know and are used to. A lot of animals are being mistagged now because that naming system just isn’t used for palmettos. I was told that the calculator might be incorrect too, but I’m not sure on that part
I wondered about this issue as well. Someone please correct me if I am wrong, but it looks like the MM gene category “Inc/Dominant Genes” is a combination of “Incomplete Dominant” and “Dominant”. If so, these should really be made in to separate categories, as these are different modes of genetic inheritance. For example, dominant gene mutations like Tessera have a homozygous/super form, but there is no phenotypic difference between a Tessera (heterozygous) and a Super Tessera (homozygous). On the other hand, incomplete dominant gene mutations like Palmetto are partially expressed phenotypically even when the animal is only heterozygous for that mutation, but are fully expressed when homozygous for a mutation. Seems like there should be a “Dominant Gene” category that has “Het” & “Super” and an “Incomplete Dominant Gene” category that has “Het” and “Visual”. Of course it would be great if the genetic calculator was up to speed on all of this as well.
I think the current tags work fine. Genetically wise (like for the calculator) it still works either way. The tags work as heterozygous and homozygous whether or not they’re dominant or inc-dom. I think palmetto’s name for each tag just needs to be changed. Het palmetto and palmetto, even if it’s inc-dom. Like I said before, it’s just like het red axanthic. Red axanthic’s page doesnt say super red axanthic
I’m sorry, but either the tags are correct or they are not. Incomplete dominant and dominant gene mutations are not the same. They do not have the same rules of inheritability, and should not be combined. If MM is passionate about doing things right, this should be fixed so that folks that don’t know the distinctions are not confused by the tags.
There are different names for it but the two forms (heterozygous and homozygous) still inherit the same. For example pinstripe (in ball pythons) is dominant (the homozygous looks the same as the heterozygous) but super pinstripes exist (even though they aren’t visibly differentiable from a heterozygous pinstripe). Recessive is similar (homozygous and heterozygous still inherit the same), but the only thing differentiating it is that it’s only visible in the homozygous form.
I think it’s fine the way it is, though I wouldn’t be opposed to the change being made. The morphpedia should help clear up confusion.
I agree that the calculator is essentially going to treat them the same, but I’d suggest that the reason we started this convo, that there is no such thing as “Super Palmetto”, is still a valid point. And Dominant and Incomplete dominant do not inherit the same, at least from the perspective of phenotype (i.e., a Het Inc. Dominant shows visually). IMO, dominant and incomplete dominant gene mutations need their own individualized sets of tags so that what is represented on MM is accurate based on science, and so that confusion is not created. MM could have left Palmetto in the recessive category and the calculator would correctly spit out the right progeny, but it would not be technically correct. MM could leave Inc. Dominant and Dominant combined, but it is not technically correct. I think MM is a great tool, and a great forum, and efforts like MorphMedia clearly show that the MM staff are passionate about educating users. I don’t think requesting that genetic info be correctly represented is an unreasonable request and in fact I think it is an important improvement that should be given consideration.
Palmetto is in fact coded as an inc dom, not a dominant. Our database makes such a distinction.
The legend in index page UI does not make such a distinction, which I imagine is where you are drawing this conclusion from. This decision was probably in part simply to keep the number of colors down to a reasonable number.
I will make a note for future redesign that it would be nice to have this distinction made. But if someone wants to learn about the gene, they can click on the (i) icon as it is next to Amelanistic, and I suspect will show up for Palmetto by tomorrow.
Although I agree that Palmetto is incomplete dominant, the heterozygous form is not always very easy to identify (and thus far, impossible or nearly impossible to identify on amel-based and hypo type morphs). What I keep seeing in ads is people listing poss het palmettos as Palmetto, since I’m assuming there is no option to choose poss het since it’s incomplete dominant? I’m wondering if adding a poss het Palmetto button could be an option. Or is it already an option and people just aren’t using it correctly?
“Palmetto is in fact coded as an inc dom, not a dominant. Our database makes such a distinction.”
That’s great that there is in fact a distinction in the coding and the database. Thanks for sharing that info John. I think if I had a vote though, I would not vote for “keeping the number of colors down to a reasonable number”. I’d suggest that consistency between the colors of tabs, the coding, actual fact, and the database is worth striving for, as that would be the best way to avoid confusion or unintentional misinformation. That is, more detail is better! Likewise, I also agree with Solarserpents that for Inc. Dominant mutations like Palmetto in which the “Het morphotypes” can be difficult or impossible to identify visually depending on what other mutations are being expressed, that a “Possible Het” button makes sense. However, hopefully most breeders will include details of possible hets in the text description.
The same thing happens in other animals in the hobby, we see it a lot in ball pythons where people cannot tell if an animal has YB or something because of all the genes in the combo. In these situations it would probably be more prudent for sellers to just not use the trait button but to mention it in the animal description.
Of course, that means that the sellers themselves have to recognize that is a better option than to use the button. It is not really something we can force anyone to do
I don’t keep corns, so I don’t have any experience with Palmettos, but if Palmetto is inc-dom, then should we be referring to the three phenotypes as “normal,” “Palmetto,” and “Super Palmetto”?
And then these problematic “poss-het Palmettos” would just be “poss-Palmettos.” In the hognose world, sometimes we see “poss-Arctic” since Arctic is inc-dom and the het phenotype can sometimes be difficult to determine.
That is how the traits are listed on MorphMarket (Palmetto and super Palmetto). However, when Palmetto was discovered, we didn’t know it was incomplete dominant, so the super form was just named Palmetto. Because the het form is often very subtle (and in some cases, impossible to tell), I would feel weird calling them Palmetto. And it is often an uphill battle trying to get names changed in the hobby! But yes, even if the options on MorphMarket were poss Palmetto, Palmetto, or super Palmetto, I think that would be a decent solution. For the poss arctic hognoses, is that an actual trait option on MorphMarket , or do people just list it in the title or description?
There is not set rule for labeling inc-dom morphs. Look at the RedAxanthic trait in ball python: normal, het Red, Red Axanthic. So it is fine to have normal, het Palm, Palmetto
Need everybody’s thoughts on this. I’ve been working with corn snakes most of my life. From speaking to a few other breeders they think the same as I do that the Palmetto Gene is a recessive gene and not an incomplete dominant. I do agree with this, but what are your thoughts on this?
There ya go @ripley500. Moved your post here. Have a read