Hey everybody, it’s been a while. Life’s been crazy but I’m still on the gecko kick. I’ve been buying bold stripe leos to start a breeding project and researching their genetics. I see “line bred” or “polygenic” used to describe bold stripes a lot, which I understand; but some sources say the bold stripe is an “incomplete recessive” trait. I’ve looked up "incomplete recessive and can’t find any specific information about it. Could one of you fantastic people shed some light for me?
Bold stripe is polymorphic (line bred is the same thing). Incomplete recessive exists in the scientific world (I personally don’t understand it) but not in the hobby.
Also, your bold stripes look great, they are a morph I would love to work with someday.
I’ve never heard of the term “incomplete recessive” used for geckos. It seems odd since Ron Tremper I thought confirmed boldstripe was a linebred trait. I don’t understand the controversy. Further down in morphpedia it says this:
This is a total guess but maybe some of the genes responsible for the patterns are recessive and some are incomplete dominant. Not all bold stripes will have mendelian genetic inheritance but some do and the genes are responsible for some of the patterns. They would still be bold stripes without the genes but the genes guarantee the patterns (so both genes are causing the same effects).
I’ve come across the term “incomplete-recessive” before and also could barely find any good information about it at all. I asked some genetics people I know and they said “some scientists coined it to mean a trait that comes from a combination of recessive alleles on two separate genes. which is DUMB if anything it should be like, double hypostatic or something”. Though it seems like some people incorrectly use it for morphs that are recessive and allelic with another morph (ex: clown and cryptic in ball pythons)
From a bit of scouring the web, Incomplete recessive, like a “simple” recessive, does not show in het form. Only when it is paired with another allelic gene, whether it be a recessive or incomplete dominant gene.
By the understanding I’m getting, its basically a recessive (no visual het) but is compatible with two separate groups.
So for a wild example in ball terms, if we found that a het Albino paired to a Pastel would create a visual “Pastino”.
So using this chart from @lmr_lmreptiles does that mean a single allele can occur multiple times and can reside on multiple allele pairs or genes (because I don’t think that’s possible)?
So if I replaced pastel with chocolate does that mean both het albino and sable (in the same complex) would be compatible in addition to het albino and chocolate? Both of those would also be in addition to het albino het candy (which are also in the same complex).
What I said might not be factually correct, I think that the dominant wild-type somewhere else on the gene would cancel out both of the hets if there is a normal in a different allele pair in the same gene with incomplete recessive. I’m learning this myself and I don’t even know what co-recessive is . Are the recessive traits in the homozygous form in different allele pairs (or alleles) or in the heterozygous form on the same allele pair (or allele)? Line-breeding is the same as selective breeding. Anything can be bred for certain effects (like different lines of tremper albino).
Incomplete recessive isn’t the correct term for allelic recessives. In cats, colorpoint and sepia (and a few others) are known to be recessive and are allelic with each other, but the relationship between the two are described as being incompletely dominant to each other. Alleles can be recessive AND incomplete dominant with other alleles
I believe what they are trying to describe. I could be wrong because it seems people are trying create verbiage to describe the interaction… But this sounds like they are saying the loci responsible for the recessive mutation is incomplete dominant with a non-allelic trait. This type of interaction has no real good description in genetics and is something we’ve come across when writing Foundation Genetics.
To sum this up the way we dedcribe it is that all non-allelic traits are incomplete dominant with each other, so an example is, Albino, Pastel. Pastel is inc-dom, albino is recessive, the phenotype is a combo that displays an Albino X Pastel, so they termed incomplete recessive to denote the phenotype interaction of 2 non-allelic traits presenting visually as incomplete dominant although they are both in the Het and Hzg forms. We can take this WAY further to dedcribe 5x combo morphs, 5 genes different loci with a mixture of recessive, incomplete dominant, and dominant mutations. The phenotype appears as an incomplete dominant of all 5 morphs mixed. Hope this helps.
Yeah epistatic reactions, from my understanding, differ in that they require background genetic information for the phenotype to present. While in the example I gave each trait can stand on their own and still produce a phenotype without the other gene being present, pastel x albino in my example.
However, if let’s say the Pastel albino animal cause a phenotype to present that wasn’t a blending of the two and produced a completely new phenotype, let’s say a purple and red animal, then I would define it as an epistatic phenotype. The more classic example would be if the animal was genetically albino from an albino x albino pairing and a 3rd unknown recessive gene being carried by both parents ended up in its complete form Hzg, producing 25-50% of the purple/red animal. That unknown gene would be something I would label as epistasis. Please correct me if I am described anything incorrectly as epistasis is more advanced in its description.
The thing that is tough here is that we have to make phenotype observations and note the way different traits react. Then, go back to how the animal was bred and test if there is the proper phenotype ratios being produced. Many observations are made to determine the dominant, Inc-dom, codom, and recessive reactions.
Your first and second paragraphs above (in the post I quoted) are two separate conversations and I have spent the better part of my lunch trying to figure out how to reconcile them independent of one another in type without sounding condescending and I still feel I am utterly failing in that regard.
Your first paragraph is specifically talking about genetic level interactions:
Put another way, mutations to Gene X behave in a recessive manner, but only in the presence of an incomplete-dominate mutation to Gene Y
You lamented that there is not a term to describe this and I corrected that there is a term and that it is “epistasis”.
Your second paragraph, however, is discussing phenotypes in combination which, at the gross level of animal paint job, are completely divorced from genetics. Your wording however, is trying to force a relationship between the two genes that does not exist and then justifying an amalgamated genetics-sounding label (incomplete-recessive) to try and legitimize the forced relationship.
The Albino Pastel phenotype has nothing to do with the two mutations interacting on a genetic level. An Albino is visually amelanistic regardless of the genetics of the Pastel locus, be it PP, Pp, or pp. Likewise, a Pastel is visually “pasteled” regardless of the genetics of the Albino locus, be it TT, Tt, or tt. Just because the combination looks different than either of the individual components alone does not mean there is a direct, genetic level interaction between them