Sex-linked pattern aberrancies?

Has anyone else had something like this happen?

The male is my Bansidhe, and this is his first proper sired clutch. The female is Torandre, my ghost girl who has given me numerous babies and never showed anything like this before. It'll be super interesting to see if this pops up next year too with the other females I'm planning on pairing him to.

But basically, the vast majority of the females (7 out of 8) are showing moderate to extreme pattern modifications. Whereas the males have only 2 out of 6 showing even mild changes.

These are the females:

"unaffected" female-


other females-

The males

"affected" males first-





unaffected males-

Fascinating! I've certainly seen sex-linked color variation, but not pattern. I look forward to your results.

-Tonya

I'll be keeping back three of these, specifically the second 'affected' male I posted, and the first two 'affected' females. End tally was 10 females, 2 of which are normal patterned and 7 males, of which 5 are normal patterned.

Sorry that this is off topic, but did you not end up getting any amel based babies in this clutch?

hypnoctopus said:

Sorry that this is off topic, but did you not end up getting any amel based babies in this clutch?

Click to expand...

that's correct, which surprised me a great deal.... So, that leaves me with a- cruddy odds (I've had one snow in a clutch of 16 eggs before of anery het amel to this same ghost) or b- the two eggs from two years ago were an attempt at parthenogenesis from the female and would explain a lot.

Next year this male is getting paired to a sulfur motley-stripe and that should prove out if he is het amel or not for sure. He's also going to my charcoal het amel ph hypo.

So now that you've mentioned this, I've been keeping my eye open for correlation between gender and pattern. I don't know this breeder, but I just happened to see their sale post and all of their non motley females have aberrant patterns, whereas none of the males do. https://www.facebook.com/1953817001528202/posts/2678864235690138/

Not a huge sample size, but I do think you're on to something.

It'll be interesting to see if this was just the world's strangest fluke, or if it is indeed genetic. Next year should prove that out when I breed him to several different females. If his daughters show up wonky again, even if just at a 50% rate, I'm probably on to something, and it's probably Z-linked.

Thanks for sharing Shiari! Definitely a fascinating topic and one that I too and very interested to investigate in the near future. However, it should be noted that the "unaffected males" pictured above do in fact all show some degree of pattern aberration. The pattern aberrations in the "unaffected males" are certainly subtle in comparison with the others in this clutch and even though there are no classic zigzagged saddles in those males, there are some aberrant lines that link saddles. Those same type of "line-linked saddles" are pictured in the photos of "affected" snakes in this clutch and those "linked saddles" are also common in other Aztec/Zigzag individuals as well (e.g., all 3 Aztecs in my collection possess this characteristic as well). So, given that there are both males and females in this clutch that display pattern aberrations, and given that there are males and females with distinct pattern aberrations in this clutch, this does not appear to be a case of a sex-linked trait. While I'm sorry to be the bearer of bad news, I don't personally think this means that figuring out the polygenetic nature of the Aztec/Zigzag mutation is any less interesting, and if any of you out there have also produced progeny with these mutations and would be willing to share your stories (i.e., info on the parents genetics, health, and age, incubation temps, problems, egg position relative to other eggs... anything that might affect pattern), I'm sure that we all could learn something interesting and hopefully have some fun in the process -Paleosmith

Yeah, the males are so minor I wasn't considering it as 'affected' as compared to the females, in part because any snake can have an aberrant saddle or two. One thing that several of them *did* have, which their father shared, is a little 'oval' mark in a saddle. I found it interesting that that passed down.

Also, the fact that any affected patterning in the males is so minor does still show a degree of sex-linking as something is suppressing that is only really present in the males.

It is absolutely possible that zigzag is sex-linked (partially or completely). There are known examples of sex-linked traits in insects, mammals and birds, but there are no proven examples of sex-linked traits in reptiles or amphibians that I am aware of. I could easily be mistaken though. It's also quite possible that the decreased levels of expression in the males in your clutch is simply by chance. I hope you will proceed with your breeding plans and let us know what you discover

I definitely will!

Thanks for your replies Shiari. I'm sure you are already aware that it has been previously suggested that zigzag could be an incubation-linked pattern aberration. While I don't personally know enough to have an opinion on that, it is well established that incubation temperature can affect all sorts of things (e.g., gender) in many reptiles, and this leaves me wondering if your clutch of eggs was stuck together with some on top and some beneath (which could contribute to small differences in temp.) ...or if you separated your eggs after they were laid. If your eggs were kept stuck together (and were layered to some degree), I wonder if it is possible that temp. differences could explain the gender-skewed distribution (potential gradient) of pattern mutations in your clutch. Fascinating stuff! I wish I had paid more attention when I took genetics

As corn sex is not linked to temperature, that should not be a factor. The eggs were clustered but the zigzagged females came from the top, middle, and bottom. They were also put in the incubator at the same time as another clutch with no pattern aberrancies at all, and aside from one kinked baby in another clutch, there was no other real abnormal patterns in *any* of the other clutches.

Thanks for your explanation. It was worth considering. Back to the drawing board I suppose. There must be some way to sort out the heritability mechanism for zigzag. I'd be interested to hear any suggestions people might have. Hopefully people will reply to this thread with their experiences and we can recognize some trend (if we manage to get enough responses).

...and I'm not absolutely convinced personally, that incubation temperature plays no role in sex determination in corns. Certainly the gender of embryos is genotypically determined, but there are records of other colubrids in which incubation temp (or fluctuations) can cause gender-reversal. I thought this was a good explanation:
http://www.cornsnakes.com/forums/showthread.php?t=128806.

I think the take home is that we still have a lot to learn about these animals (thankfully. The recently discovered sex chromosome complexity of henophidians is a good example. I don't think any biologist would have guessed that one 10 years ago!

https://www.sciencedirect.com/science/article/pii/S0960982217308527

Shairi, that's interesting. I was talking to someone else about this, who said it appears to be true about it being sex linked.
Looking back, all of the aberrant pattered babies I have produced or owned have been female.

This is the last one I produced, two years ago.
In 2011, when I started my Miami Tessera projects, one clutch had 3 aberrant babies, all females.

Apologies if this sounds contrary... my only interest is in exchanging info and hopefully learning something. I do however, think I can offer some food for thought on this topic. While it is possible that zigzag is sex-linked and was only associated with females in your specific clutches/experience, it is highly unlikely. I have a male zigzag in my collection. I just purchased a female zigzag from a breeder in PA who kept back multiple male and female zigzags from that same clutch for breeding... and while it seems to be gone now, there were male Ultramel Aztecs listed for sale on the VMS site until very recently (I purchased one of the females from the clutch). And again, all of the newborns in Shiari's clutch display some degree of pattern aberrancy. Where one draws the line between aberrant enough to call it a zigzag or an aztec seems to be ambiguous. I have seen sources that say zigzag and aztec are the same thing, sources that say they are separate morphs, and sources that say Aztec is the refined form of zigzag. In short, the jury is still out on this mystery. Is it possible that there are clutches of sex-linked zigzags in which only one gender is aberrantly patterned.... AND clutches in which male and female zigzags are produced in a single clutch? Yes, sure, incredibly doubtful but perhaps. Genetics is ridiculously complex at times. However, the odds of that being the case are astronomically small. I hope you prove me wrong and we all learn something in the process but I would strongly suggest that based on the evidence we have currently, zigzag is not sex-linked and you would be better off directing your efforts trying to determine if it is inherited in some other polygenetic fashion.

Okay, look. You are not merely sounding contrary. You are outright *being* contrary.

Not all zigzag is heritable. Most of the time it's just a pattern whoopsie.

These individuals have lavender heritage, and specifically a line that is VERY known for throwing zigzags.

Not one of the males would ever be called a zigzag or partial zigzag. All the females but one are.

Females are genetically ZW. Males are genetically ZZ. Temperature does NOT play a role in sex in corns, people would have noted that by now and as I have raised clutches both at the 78-80 range and the 83 to 85 range and never seen a particular sex be dominant over the other in the last 10 years, this is NOT a thing.

If only the females are showing any real degree of pattern abnormality beyond the norm, as many corns have a funky saddle or two, then there may be something linked to the Z chromosome. As males have 2 Zs, then the unaffected chromosome could be having a suppression effect.

There's a reason I put a question mark on this, I'm not saying it's absolutely 100% what's going on. It's a curiousity and speculation and I'm going to be breeding this male again next year to see what happens.

Are we DONE yet?

Unlike you, I am more interested in learning than being right... so yeah we are done. Supposedly this is a site for conversations about corn snake related issues, not a site where those with the most posts feel free to bully others and evidently are threatened by facts that don't necessarily agree with their opinions... opinions based on limited knowledge, conjecture, and anecdotal evidence.