Proving Dominant Traits

[Nick Mutton]

Your free to believe whatever you like but this stuff is not magical or even mysterious and there is a reason why nobody breeds spider X spider or Pin X pin etc. You are also making the assumption that everyone has always been honest, which most people realize has not been the case either.

Hiding behind the "we dont know" is a tad convenient, as with a lethal gene that dies early in development, the proof you demand would be impossible to get. Over the years when this argument comes up I usually find it a amusing that those who argue that Spider is dominant avoid doing that pairing in their own collections.

We now have a whole group of genes, that when paired result in severely damaged or dead combos (spider, woma, hg woma, sable, champ etc) and of these the spider is by far the MOST damaged in heterozygous form. So even though we know that the spider gene is clearly lethal in several combos, AND there is a complete lack of any evidence for a viable homozygous form. I guess I dont understand your relentless optimism on the subject.

On the issue of Dominant genes, I hardly think the "daddy" gene counts as it looks normal in both heterozygous and homozygous form. On the congo, can you even define what a "congo" looks like.... me neither.
Your then left with one supposed homozygous pin when there should certainly be many more than one. call me a skeptic I guess.

[reptileexperts]

My thoughts on that as well with BHBs claim is it could've been a money game as well. Brian found the original pin and proved it out. It would be better for business to find a "dominate" trait, rather than another lethal homozygous. I'll email brian and ask him why he hasn't proven out another homozygous. It is more likely that a) ONE survived as Homozygous or b) he did hit those odds of all pinstripes.

And like Nick Said, we can't hide behind we don't know, because we do, we see clutch reports, and if someone somewhere had hit the homozygous version we would know! its not 1/16 chance, its 1/4 when you breed the two together, Brian at BHB Im positive has breeding data for pin to pin with what only ONE possible case that it proved out to be possibly homo? What about the other clutches from that individual? Why only quote one clutch? That's odd because Brian would breed multiple generations out of that because he could produce a TON of pins easy. . . So forgive my speculation on the matter, not trying to insult anyone with this topic, this is high school level thought concepts, we just need to think of it realistically.

[reptileexperts]

Also concerning your het odds, how many people breed het pied to het pied and end up with usually a pied in the first generation of the cross? The probability seems off in your table . . . Not exactly sure what your were trying to prove out, because if you know anything about probability each egg is independent, it rolls its own dice, you have the same probability of getting every egg Homo or every egg Het or every egg normal. SAME. But each egg has the same variable of probability, 25%, 25%, 50%, so your chart does little to prove anything . . .

[gsarchie]

Love the different opinions and everyone's ability to play nicely in this thread (so far)!! I won't say much as to avoid beating too many dead horses but I will say the following:

1) As to the homozygous spider, we truly do not know, and to say otherwise is incorrect, plain and simple.

2) No one has mentioned that a lethal combination doesn't have to be a slug egg, which suprises me! In the case of Spiders - If it is lethal when sperm first combines with an egg then no egg will be laid, slug or otherwise, as the female can simply absorb the egg back into her body and make good use of the nutrients on the remaining healthy eggs!! If sperm isn't even able to fertilize an egg with the same allele(prezygotic exclusion) then a sperm with a normal set of DNA could do the job instead, producing a viable spider egg.

While you may not agree, keep in mind that my BS is in a biological field and that I have taken both genetics and biological statistics at the college level. As a result I feel like what I have to say should hold some wieght. Whether you agree with what I said or not doesn't matter to me either way, I just wanted to weigh in.

To the OP - thanks for a thought provoking post! It is by raising interesting questions that cause us to seek answers that ultimately broadens our knowledge base (so long as we are open to what we find, whether it is what we expected to find or not!)

[reptileexperts]

1) We do know, we fail to acknowledge, if its not produceable, its lethal - why is it a unknown? People like BHB breed these things by the thousands, and keeps detailed records of all accounts. I'm positive he has the proof that it is lethal, but because its bad for business I think he isn't openly giving this information, but because he's not a bad guy and is interested in supporting the community, I promise he'd give it if he's directly asked for it. Remember the lack of evidence of a homozygous form proven out over multiple generations, is the proof.

2) This is true. We don't have to see slugs for there to have been infertile eggs that didn't even make it that far in the process.

[paulh]

Keeping records is one thing, going back and analyzing those records is something else. Analysis take time, and sometimes nobody gets around to doing it. It happens to the academics as well as breeders.

I don't see why people agonize over lethal genes. If you don't like the looks of the heterozygote, don't get it. If the homozygote dies before hatching, tough bananas for it, but everything dies sooner or later. Even if the heterozygote is less vigorous than the normal, breeding from the heterozygotes can produce better than average normals. Because the rest of the genetics has to be a bit better to offset the bad effect of the mutant gene.

[Anatopism]

Your free to believe whatever you like but this stuff is not magical or even mysterious and there is a reason why nobody breeds spider X spider or Pin X pin etc. You are also making the assumption that everyone has always been honest, which most people realize has not been the case either.

Hiding behind the "we dont know" is a tad convenient, as with a lethal gene that dies early in development, the proof you demand would be impossible to get. Over the years when this argument comes up I usually find it a amusing that those who argue that Spider is dominant avoid doing that pairing in their own collections.

We now have a whole group of genes, that when paired result in severely damaged or dead combos (spider, woma, hg woma, sable, champ etc) and of these the spider is by far the MOST damaged in heterozygous form. So even though we know that the spider gene is clearly lethal in several combos, AND there is a complete lack of any evidence for a viable homozygous form. I guess I dont understand your relentless optimism on the subject.

You are also assuming that everyone involved in any spider project must be dishonest. Can I ask, what is the motivation to be dishonest in the case of a lethal homozygous spider at this point? Seriously... Do you think big time breeders will "take a hit" by stating that homo spider is lethal, and suddenly their $10,000 spiders that they've been selling left and right will suddenly only sell for around $150? Oh wait.. they already sell for that much. They already sell hetero spiders, and everybody still buys them, despite their potential flaws. They still remain popular base morphs and combos. Is there some business gain I'm missing, from "hiding the truth" about spiders?

The simple fact is that we don't KNOW. Evidence may point towards one direction, but until a project is done to specifically prove out that the homozygous spider is lethal or otherwise, we simply don't know. People aren't arguing that it isn't lethal, simply that we don't know for a fact. We have theories and evidence that suggest a conclusion, but do not prove a conclusion.


CORRELATION != CAUSATION, and until a proper "study" has been made, we don't know, we can only make educated guesses in the most probable direction. Take note of the following sentence really quickly: The former thought applies to 'both sides' of the debate. This is not an argument FOR homozygous spider being alive and healthy. It is an argument for proper procedure, and use of the scientific method.



As for why people aren't trying to prove homozygous spider, or any other perceived dominant morph:

To say that it's because people are afraid it is lethal, and that this contributes towards "proof" that people are being dishonest and therefore "proof" that spider is lethal...... well that's a fallacy and a half. My ONLY motivation for now wanting to get into a homozygous spider project is to provide evidence towards either conclusion - as I don't care whether homo spider is lethal or not, I just want people to stop saying they KNOW based off correlational data.

I feel another poll coming on, as I'd like to know how many people don't get into a homo spider project because of whether they think it's lethal and are afraid of wasting time. I wonder if people don't get into the project because it IS a waste of time, and by the time a homo spider would be proved out (or proved to be lethal) they could have produced several more spiders, and spider combos. The amount of resources and time needed to accurately record data on this topic, is limited to a very select number of breeders. The average hobbyist breeder doesn't have time, space, or resources to put into a project that has two basic outcomes:
1) a lethal homozygous spider, time wasted, other than to contribute to the "debate" on the topic.
2) a homozygous spider that can pass on spider to all of it's offspring. Neat... so now you can make sure every morph it's put to also has spider added... How many more spider combos could you have made in the process? Having a homozygous spider HANDED do you would maybe provide a benefit.. but going through the effort of producing one, is a considerable waste of time.

[OhhWatALoser]

Your free to believe whatever you like but this stuff is not magical or even mysterious and there is a reason why nobody breeds spider X spider or Pin X pin etc. You are also making the assumption that everyone has always been honest, which most people realize has not been the case either.

nobody breeds dominant traits because of the time/money/proving out/ect. for a morph that looks exactly like the het. It's alot easier to breed two pastels together and say thats a homozygous pastel. All a homozygous dominant trait does is give you genetic powerhouse, but phenotypes is what makes money, as a big breeder, what are you going to go after? It only makes sense.

Hiding behind the "we dont know" is a tad convenient, as with a lethal gene that dies early in development, the proof you demand would be impossible to get. Over the years when this argument comes up I usually find it a amusing that those who argue that Spider is dominant avoid doing that pairing in their own collections.

yup we are hiding behind something... instead of assuming, how dare we. Ultra sound and follow egg development, if it dies early you will see it. It's not impossible, just difficult, time consuming, and a lot of record keeping. Also whos arguing it's dominant? Thats never been proven.

We now have a whole group of genes, that when paired result in severely damaged or dead combos (spider, woma, hg woma, sable, champ etc) and of these the spider is by far the MOST damaged in heterozygous form. So even though we know that the spider gene is clearly lethal in several combos, AND there is a complete lack of any evidence for a viable homozygous form. I guess I dont understand your relentless optimism on the subject.

Its no optimism or anything, I want evidence before we say something is fact, so far the evidence is lack of evidence. I'll stick with the truth of we don't know.

On the issue of Dominant genes, I hardly think the "daddy" gene counts as it looks normal in both heterozygous and homozygous form. On the congo, can you even define what a "congo" looks like.... me neither.
Your then left with one supposed homozygous pin when there should certainly be many more than one. call me a skeptic I guess.

het daddys and normals from the same clutch are easy to pick out, at least it was in the one clutch I saw. Subtle no doubt, I could never look at a snake and say, yes that is het daddy, but they are different. As for congo, brighter, and more yellow than a normal. Again it may be subtle, but still a dominant trait. You're grasping at straws to prove your point if you ask me... I'm sorry yes, there is dominant traits in the ball python world... OMG!

My thoughts on that as well with BHBs claim is it could've been a money game as well. Brian found the original pin and proved it out. It would be better for business to find a "dominate" trait, rather than another lethal homozygous. I'll email brian and ask him why he hasn't proven out another homozygous. It is more likely that a) ONE survived as Homozygous or b) he did hit those odds of all pinstripes.

See above.... time, money, space, females, for animal that looks exactly the same... yea im on repeat.

And like Nick Said, we can't hide behind we don't know, because we do, we see clutch reports, and if someone somewhere had hit the homozygous version we would know! its not 1/16 chance, its 1/4 when you breed the two together, Brian at BHB Im positive has breeding data for pin to pin with what only ONE possible case that it proved out to be possibly homo? What about the other clutches from that individual? Why only quote one clutch? That's odd because Brian would breed multiple generations out of that because he could produce a TON of pins easy. . . So forgive my speculation on the matter, not trying to insult anyone with this topic, this is high school level thought concepts, we just need to think of it realistically.

your not thinking of this as a business person, phenotypes sell. BTW if you didn't notice.... he does sell a ton of pins easy. Maybe here is another point you guys are missing. Ok I make my homozygous pinstripe, awesome. Now I want to mix it with another morph... the whole proving out process starts all over again, only way you can guarantee it is homozygous, is to breed 2x already proven homozygous together. so you can't mix in other morphs without starting the entire LONG process over again. again phenotypes sell. It's not like a normal het x het, theres a long process everytime.

Also concerning your het odds, how many people breed het pied to het pied and end up with usually a pied in the first generation of the cross? The probability seems off in your table . . . Not exactly sure what your were trying to prove out, because if you know anything about probability each egg is independent, it rolls its own dice, you have the same probability of getting every egg Homo or every egg Het or every egg normal. SAME. But each egg has the same variable of probability, 25%, 25%, 50%, so your chart does little to prove anything . . .

the chart is breed a het to a normal, 50% chance each egg. and what are the chances of missing 50% 5 times? 10 times? 15 times? 20 times? 25 times? 27 times? refer to the chart and my above posts.

[RandyRemington]

I know TSK is years and years into a spider X spider project. Their numbers aren't huge but they probably have by far the best records on the subject so if anyone here knows them maybe they can ask if they are ready to share. Does NERD or BHB even bother to keep records on everything? As a very small scale breeder I find it a nuisance and could easily see some of the big guys not bothering but of course don’t know any of them, just have a few old e-mails from TSK indicating they are records nuts. I just never had any reason not to believe BHB's report of the homozygous pinstripe because of the data he presented to back it up and even though NERD denied that spider was homozygous lethal years ago he didn't really present any data so I discounted it as meaning he just didn't see any dying hatchlings like with the woma/pearl. Anyway, I don't really want to get a 2nd spider and embark on the work to try to prove what might be unprovable for myself but could see getting my first pinstripe pair to try that one, maybe. Suppose at this point you would want some sort of homozygous pinstripe combo to make the project work economically and that complicates things.

[OhhWatALoser]

I know TSK is years and years into a spider X spider project. Their numbers aren't huge but they probably have by far the best records on the subject so if anyone here knows them maybe they can ask if they are ready to share. Does NERD or BHB even bother to keep records on everything? As a very small scale breeder I find it a nuisance and could easily see some of the big guys not bothering but of course don’t know any of them, just have a few old e-mails from TSK indicating they are records nuts. I just never had any reason not to believe BHB's report of the homozygous pinstripe because of the data he presented to back it up and even though NERD denied that spider was homozygous lethal years ago he didn't really present any data so I discounted it as meaning he just didn't see any dying hatchlings like with the woma/pearl. Anyway, I don't really want to get a 2nd spider and embark on the work to try to prove what might be unprovable for myself but could see getting my first pinstripe pair to try that one, maybe. Suppose at this point you would want some sort of homozygous pinstripe combo to make the project work economically and that complicates things.

Would be awesome for someone to come out with some data on the spider. I'm quite surprised a big breeder would work on it, glad they are trying.


I also thought about shooting for a high end pinstripe pair and going from there..... its not economicly feasible imo, compared to using another morph that is not dominant. The glory of doing it and having a genetic powerhouse that no one else has and can't have for many years.... has a certain cool factor to it. I still might, just need to find the right pinstripe female... maybe something with some hypo in it to go with my lemonblast het hypo male....see what this year brings.