I did a write up on the spider, double check it for me?

I made a write up for the homozygous spider for myself and while I was at it the wobble also, guess its kinda like a faq. Do you guys see anything untrue or some important info thats missing? Now I don't really want to start a debate, I feel as I would have address all issues so there really should be room for a debate, but there always seems to be anyways.....

The Spider Ball Python

There is a lot going on with this morph besides just the sweet pattern. There are 2 issues that are highly debated surrounding this morph. I will try to address both. First is homozygous spider and the apparent neurological issue known as "the wobble."

The Homozygous Spider

If the spider is a simple dominate gene and I bred a spider x spider, I should statistically get 25% Homozygous Spider, 50% Heterozygous Spider, 25% Normal. The homozygous spider should look exactly like a heterozygous spider. The only difference would be, the homozygous spider, when bred to any other ball python, the offspring would all be spiders, while the heterozygous spider, the offspring would only have a 50/50 chance.

Here's the problem, the spider was first established at NERD in 1999, and we still have yet to see a proven homozygous spider. Now before we get into all the theory, Kevin (the owner of NERD), they guy that imported the first and has dealt with more spiders than anyone else, has to say about the issue. Kevin said that he has not produced and does not believe that there is a homozygous spider nor that spider is homozygous lethal. From what I understand he is saying it just simply does not exist for an unknown reason and is not a simple dominate gene. Correct me if I'm misunderstanding him.

Another theory is that homozygous spider is lethal, which is based on the fact that we haven't seen one yet, which is a pretty weak theory in my opinion, but not totally dismissible. I do think this theory could be put to rest by some spider x spider pairing being done and keeping an eye on the follicles of the females, if somewhere around 25% of them die/reabsorb/not hatch, it may strengthen this theory, but I think people would want to see a lot of eggs before we call it "fact." Which would be a lot of resources to waste for a big breeder to try. so don't expect it any time soon. I think the only chance of proving this, is us small breeders trying it out and all of us putting our data together.

Another theory, there hasn't been enough spider x spider breedings to prove/disprove a homozygous spider. Well here's the deal with this, you first have a breed a spider x spider. every spider offspring only has a 33% chance to be homozygous. then you have to raise that snake up and do multiple breedings to prove it is in fact homozygous, opposed to you just getting really lucky on a clutch. So yes very difficult to prove.

Not many people have the resources to do this, NERD has tired to prove it but as far as I know, they don't have any public statement about what they did to try to prove the homozygous spider. So I guess it leaves this theory open ended. more info would sway my opinion one way or another. Tho if Kevin said he did enough breedings, he most likely did enough breedings.


Now the question, "If I bred a spider x spider, statistically what % of spider should I get?" Well If homozygous spider does exist and is dodging us all these years, 25% homozygous/50% heterozygous/25% normal, if its homozygous lethal then 66% heterozygous/33% normal. If it doesn't exist for some reason, depending on how you look at it, it could either be 66% heterozygous/33% normal or 75% heterozygous/25% normal. So go ahead pick one. :)

The Wobble

Anyone who owns a spider or seen on in person most likely already knows what I'm talking about here. The spider has an apparent neurological issue, which I think the best way to describe it, they lose their equilibrium. You may not even see it, it can be a subtle as them just tilting their head once in a while, shaking in their head or it can be as bad as them corkscrewing their body in the air almost uncontrollably. It could only happen during feedings or other exciting situations for the snake or it could just be a constant thing. could have no signs as a baby and show it as an adult or have it as a baby and grow out of it.

What I am getting at is, this is very variable, every spider is different.

Search "spider ball python wobble" on youtube and you can see some of the extreme cases of the spider wobble. Now I will say most spider are no where near as bad as the typical ones you see on the net. Don't let those select few deter you from this morph. Most are not bad at all.

The wobble is linked to the spider gene. The normals that come out of the same clutch as spiders don't have the wobble, just the spiders. Also adding morphs does not fix the spider wobble. Anything with spider in it, whether it be a bumblebee, spinner, or one of NERD's crazy creations, they have the wobble.

Breeding a low wobble spider can result in some offspring with a bad wobble, breeding a bad wobbling spider can result in low wobbling offspring. There appears to be no way to selectively breed it out also.

Also, if I hear one more person make a claim that inbreeding may cause the wobble, I think im going to scream. I will be bold and say the spider is the most out-crossed morph in the ball python world. There is no proven homozygous spider, so spider x spider breeding are very rare. So no you are wrong, it is in no way related to inbreeding.

So then questions come up such as, "Why would you breed a snake with a defect?" and "What if my snake can't eat because of it?" We breed them because its a morph, every morph is a "defect," do you think a bright white ball python would fair to well in Africa? They are only going to remain in captivity and they eat, poop, breed, live healthy lives just like any other ball python in captivity. I don't see the problem. If you don't like them, no one is forcing you to own or like them, but don't you dare make a claim that there is something wrong with others owning them. It's extremely closed minded and Hypocritical.

In all of my research, I have only found 1 person that makes a claim that they had a baby with a wobble that was so bad, it could not eat. 1 person out of the multiple-thousands of snakes out there. Also I personally would of liked that snake to go under someone else's care to see if something could be done, but I don't know details of the situation. So I guess if you have one they cannot eat, by design it will not be around. But besides the one case, they all eat, poop, breed, and live healthy lives in captivity.

That's a great write-up...don't see anything there I would disagree with. Also agree that if there was a Homozygous Spider, NERD would have found out by now...and I imagine would have spilled the beans...I know there's a lot of secrecy in this hobby, but not sure why they'd keep that one a secret...

I have heard of woma wobble. I dont remember when i read it or what thread. But im pretty sure it was something to do with the hiddengene womas. Someone correct me if im wrong, like i said, i dont remember the whole thing as i can barley remember yesterday. But good write up.

Sent from my HUAWEI-M860

The spider gene is something called recessive lethality. Now I know you're going to say "but it's dominant" but let me explain. Capitol X will represent the spider gene, and x will represent a normal gene.

Recessive lethality means that the trait (in this case, the spider gene) shows in a heterozygous animal (making the gene 'act' dominant in nature).
[Xx] - Living spider.

However, when the animal is homozygous for the spider gene [XX], the animal dies before it is born. Thus, the lethality is recessive because the gene needs both alleles in order for the lethality to take place (death of the animal). This makes the gene recessive for death, but dominant acting with a heterozygous individual [Xx] but it can still produce normals [xx]. Normals seem less common because of the lethality and the ratio favors the spider gene.

1:2:1 (XX:Xx:xx) And since [XX] dies, you only see the 2:1 ratio of spiders:normals.

Hope that can clear things up a little bit. This is something that I brought up under deep discussion in my genetics class.

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Originally Posted by blackcrystal22

The spider gene is something called recessive lethality. Now I know you're going to say "but it's dominant" but let me explain. Capitol X will represent the spider gene, and x will represent a normal gene.

Recessive lethality means that the trait (in this case, the spider gene) shows in a heterozygous animal (making the gene 'act' dominant in nature).
[Xx] - Living spider.

However, when the animal is homozygous for the spider gene [XX], the animal dies before it is born. Thus, the lethality is recessive because the gene needs both alleles in order for the lethality to take place (death of the animal). This makes the gene recessive for death, but dominant acting with a heterozygous individual [Xx] but it can still produce normals [xx]. Normals seem less common because of the lethality and the ratio favors the spider gene.

1:2:1 (XX:Xx:xx) And since [XX] dies, you only see the 2:1 ratio of spiders:normals.

Hope that can clear things up a little bit. This is something that I brought up under deep discussion in my genetics class.

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I'm far too dumb to understand all that...:rolleye2:

If I breed two spiders together, will half the babies (or eggs) be slugs, or will they not even be laid...i.e...be reabsorbed before being laid?

Quote:

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Originally Posted by blackcrystal22

The spider gene is something called recessive lethality. Now I know you're going to say "but it's dominant" but let me explain. Capitol X will represent the spider gene, and x will represent a normal gene.

Recessive lethality means that the trait (in this case, the spider gene) shows in a heterozygous animal (making the gene 'act' dominant in nature).
[Xx] - Living spider.

However, when the animal is homozygous for the spider gene [XX], the animal dies before it is born. Thus, the lethality is recessive because the gene needs both alleles in order for the lethality to take place (death of the animal). This makes the gene recessive for death, but dominant acting with a heterozygous individual [Xx] but it can still produce normals [xx]. Normals seem less common because of the lethality and the ratio favors the spider gene.

1:2:1 (XX:Xx:xx) And since [XX] dies, you only see the 2:1 ratio of spiders:normals.

Hope that can clear things up a little bit. This is something that I brought up under deep discussion in my genetics class.

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doesn't mean its recessive, in fact, if thats the case it would be co-dom. Recessive means the heterozygous form does not show, which it obviously does, the spider we all have in our collections.

co-dom means the heterozygous and homozygous form are different. which if it was lethal, het would be spider and homozygous would be dead. still homozygous lethal anyways. the "XX" means homozygous, has nothing to do with recessive, co-dom, or dom.

Way I see it, it doesn't change the odds, sure it changes the ratio of things that actually come out of eggs, but as far as follicles go you still have the 1:2:1 ratio.

That's assuming its even homozygous lethal which there is next to nothing that suggests this lol.

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Originally Posted by sho220

I'm far too dumb to understand all that...:rolleye2:

If I breed two spiders together, will half the babies (or eggs) be slugs, or will they not even be laid...i.e...be reabsorbed before being laid?

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There nothing that suggests that anything would happen to the eggs

as far as no homozygous form existing.... It is a gene that affects an allele with locusts..... just like everything else.... To think that there is no way for an animal to inherit a gene from both parents is ridiculous...... I dont know if the homozygous form is lethal, I personally dont think any of us do... The woma gene is homozygous lethal we see the offspring fail to thrive.... There are a million threads on homozygous lethal spider and the only conclusion we ever seem to come up with is simply we dont know.... As far as recessive lethal we would not see the spider pattern show in a heterozygous animal if the gene was recessive.

http://en.wikipedia.org/wiki/Dominance_(genetics)

http://en.wikipedia.org/wiki/Gene

http://en.wikipedia.org/wiki/Zygosity

http://en.wikipedia.org/wiki/Allele

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Originally Posted by OhhWatALoser

THE guy that imported the first and has dealt with more spiders than anyone else, has to say about the issue.

I do think this theory could be put to rest by some spider x spider pairingS being done and keeping an eye on the follicles of the females, if somewhere around 25% of them die/reabsorb/not hatch, it may strengthen this theory, but I think people would want to see a lot of eggs before we call it "fact." Which would be a lot of resources to waste for a big breeder to try. So don't expect it any time soon. I think the only chance of proving this, is us small breeders trying it out and all of us putting our data together.

Another theory, there hasn't been enough spider x spider breedings to prove/disprove a homozygous spider. Well here's the deal with this, you first have a breed a spider x spider. Every spider offspring only has a 33% chance to be homozygous. Then you have to raise that snake up and do multiple breedings to prove it is in fact homozygous, opposed to you just getting really lucky on a clutch. So yes very difficult to prove.

More info would sway my opinion one way or another. Tho if Kevin said he did enough breedings, he most likely did enough breedings.



Anyone who owns a spider or seen onE in person most likely already knows what I'm talking about here. The spider has an apparent neurological issue, which I think the best way to describe it, they lose their equilibrium. You may not even see it, it can be aS subtle as them just tilting their head once in a while, shaking in their head or it can be as bad as them corkscrewing their body in the air almost uncontrollably.

Also, if I hear one more person make a claim that inbreeding may cause the wobble, I think I'm going to scream.

We breed them because its a morph, every morph is a "defect," do you think a bright white ball python would fair TOO well in Africa? If you don't like them, no one is forcing you to own or like them, but don't you dare make a claim that there is something wrong with others owning them. It's extremely closed minded and Hypocritical.

In all of my research, I have only found 1 person that makes a claim that they had a baby with a wobble that was so bad, it could not eat. 1 person out of the multiple-thousands of snakes out there. Also I personally would of liked that snake to go under someone else's care to see if something could be done, but I don't know details of the situation. So I guess if you have one they cannot eat, by design it will not be around. But besides the one case, they all eat, poop, breed, and live healthy lives in captivity.

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Idk if when you posted this and asked for someone to double check, you meant double check for grammatical errors, but I went ahead and checked that. W.e I put in bold are words I found that could be fixed, I think in most of the boldings I put the already corrected word or what not. Sorry if this is nto what you were asking for, either way, great post.

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Originally Posted by that_dc5

Idk if when you posted this and asked for someone to double check, you meant double check for grammatical errors, but I went ahead and checked that. W.e I put in bold are words I found that could be fixed, I think in most of the boldings I put the already corrected word or what not. Sorry if this is not what you were asking for, either way, great post.

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I didn't exactly mean grammatical errors, but obviously I needed it lol thx

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Originally Posted by mainbutter

http://en.wikipedia.org/wiki/Dominance_(genetics)

http://en.wikipedia.org/wiki/Gene

http://en.wikipedia.org/wiki/Zygosity

http://en.wikipedia.org/wiki/Allele

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???

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Originally Posted by OhhWatALoser

doesn't mean its recessive, in fact, if thats the case it would be co-dom. Recessive means the heterozygous form does not show, which it obviously does, the spider we all have in our collections.

There nothing that suggests that anything would happen to the eggs

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You're misunderstanding blackcrystal's post. Recessive lethality does not mean that the spider gene is recessive. (And herein lies the problem with the traditional Mendelian classification system of dominant/recessive/co-dom, etc. -- it is WAY too simple to adequately explain genetics as we now understand it, and gets really confusing.)

What it would mean is that whatever causes the homozygous spiders to not be born -- the lethal part -- is recessive. We know that's recessive because heterozygous spiders are alive, and homozygous ones are not.

Basically, you're breaking down the different effects of the one single "spider" gene (the pattern part and the lethal part, whatever that may be) into two separate categories and saying that the spider pattern is dominant while the lethal whatever is recessive, even though they are caused by the same gene. (This is called pleiotropy, when one gene has multiple different effects.)

I like that theory, although I could also argue that the homozygous lethal condition may actually be an effect of the co-dominant neurologic part of the spider gene -- ie, in heterozygous form they are deficient in some protein, and that deficiency causes them to wobble, spin, etc., while in homozygous form they have none of that protein at all and so fail to progress past early embryogenesis.

I also agree with jjmitchell's post (except for the last line; see above) in that I don't see how it's possible for a homozygous spider to just not exist. Now, that IS what I've heard Kevin postulate, and it's also what I was told by another breeder who worked with spiders very early on (that breeder also claimed that spider x spider produced 100% spiders every time, which I don't particularly believe). I just don't buy it, though -- at some point if you breed spider x spider, a sperm with the spider gene is going to meet an egg with the spider gene and something is going to happen. Maybe the embryo forms and then dies (lethality), but something has to happen.

I mean, if someone can think of a reason why a spider sperm and spider egg may just never meet, please let me know; I just can't really picture it. :confused:

I really do wonder, though, if we've really honestly done enough spider to spider breedings to say conclusively. It does seem like, after all this time, if a homoz. spider was alive and breeding we would've heard of it. That having been said, how many people really breed spider x spider? As you said, I do believe that they are one of the most outcrossed mutations ... And heck, there's only one homozygous pinstripe that we all know of, and we all know of it because it's owned by a breeder who also does an Internet show, and is very vocal and active within the community. What if the one or two homozygous spiders out there just happen to be owned by breeders who don't get on the Internet that much? :rolleyes:

Also, if you are looking for criticism on the writeup in general, I think that the last couple of paragraphs regarding the wobble come off as a bit defensive. I have spiders, but at the same time I do think there is a lot of room for debate on the ethics of propagating them. I don't think it is fair to brand those who are opposed to their propagation as closed-minded and hypocritical.

I think that it might be better to explain that the majority of spiders have very minor clinical signs, eat and breed great (suggesting that they are thriving, unlike the pearl), and that the severely affected animals are few and far between. Let readers draw their own conclusions as to the ethics of breeding spiders -- those who are against it will continue to be against it regardless of your "official" position in the writeup, and taking up a defensive position looks a bit confrontational IMO.

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Originally Posted by Serpent_Nirvana

That having been said, how many people really breed spider x spider?

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Maybe not now, but early on??? Probably just about everyone that had a male and female Spider of breeding size/age...Who wouldn't want to create a Super Spider...?

Quote:

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Originally Posted by Serpent_Nirvana

You're misunderstanding blackcrystal's post. Recessive lethality does not mean that the spider gene is recessive. (And herein lies the problem with the traditional Mendelian classification system of dominant/recessive/co-dom, etc. -- it is WAY too simple to adequately explain genetics as we now understand it, and gets really confusing.)

What it would mean is that whatever causes the homozygous spiders to not be born -- the lethal part -- is recessive. We know that's recessive because heterozygous spiders are alive, and homozygous ones are not.

Basically, you're breaking down the different effects of the one single "spider" gene (the pattern part and the lethal part, whatever that may be) into two separate categories and saying that the spider pattern is dominant while the lethal whatever is recessive, even though they are caused by the same gene. (This is called pleiotropy, when one gene has multiple different effects.)

I like that theory, although I could also argue that the homozygous lethal condition may actually be an effect of the co-dominant neurologic part of the spider gene -- ie, in heterozygous form they are deficient in some protein, and that deficiency causes them to wobble, spin, etc., while in homozygous form they have none of that protein at all and so fail to progress past early embryogenesis.

I also agree with jjmitchell's post (except for the last line; see above) in that I don't see how it's possible for a homozygous spider to just not exist. Now, that IS what I've heard Kevin postulate, and it's also what I was told by another breeder who worked with spiders very early on (that breeder also claimed that spider x spider produced 100% spiders every time, which I don't particularly believe). I just don't buy it, though -- at some point if you breed spider x spider, a sperm with the spider gene is going to meet an egg with the spider gene and something is going to happen. Maybe the embryo forms and then dies (lethality), but something has to happen.

I mean, if someone can think of a reason why a spider sperm and spider egg may just never meet, please let me know; I just can't really picture it. :confused:

I really do wonder, though, if we've really honestly done enough spider to spider breedings to say conclusively. It does seem like, after all this time, if a homoz. spider was alive and breeding we would've heard of it. That having been said, how many people really breed spider x spider? As you said, I do believe that they are one of the most outcrossed mutations ... And heck, there's only one homozygous pinstripe that we all know of, and we all know of it because it's owned by a breeder who also does an Internet show, and is very vocal and active within the community. What if the one or two homozygous spiders out there just happen to be owned by breeders who don't get on the Internet that much? :rolleyes:

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you guys can't call phenotypes different things whent hey are caused by the same gene. while gene cause different phenotypes. we classify genes as recessive, co-dom and dom, not phenotypes.

you can't call the lethal part (if it exists) recessive unless you call super pastel also recessive because it doesn't show in the heterozygous form. this is not how we classify genes.... im sorry its just not. spider is dominate as of now, if we find out its lethal in homozygous(super) form its co-dom. i mean its the exact definition of co-dom, different phenotype in between heterozygous (spider) and homozygous (dead).

While i agree with the rest of what you said is possible, nothing points to it except "we havn't seen one yet" so that about where the debate ends as far as i can see

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Originally Posted by Serpent_Nirvana

Also, if you are looking for criticism on the writeup in general, I think that the last couple of paragraphs regarding the wobble come off as a bit defensive. I have spiders, but at the same time I do think there is a lot of room for debate on the ethics of propagating them. I don't think it is fair to brand those who are opposed to their propagation as closed-minded and hypocritical.

I think that it might be better to explain that the majority of spiders have very minor clinical signs, eat and breed great (suggesting that they are thriving, unlike the pearl), and that the severely affected animals are few and far between. Let readers draw their own conclusions as to the ethics of breeding spiders -- those who are against it will continue to be against it regardless of your "official" position in the writeup, and taking up a defensive position looks a bit confrontational IMO.

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maybe if i put the words "I feel" in front of it? tho it is pretty much the definition of hypocritical lol. and yes this is exactly what i was looking for ty

how would you feel it reworded this way... If you don't like them, no one is forcing you to own or like them, but if you think there is something wrong with others owning them, I feel that is closed minded and hypocritical. This morph has been doing great in the ball python world since 1999

Quote:

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Originally Posted by OhhWatALoser

maybe if i put the words "I feel" in front of it? tho it is pretty much the definition of hypocritical lol. and yes this is exactly what i was looking for ty

how would you feel it reworded this way... If you don't like them, no one is forcing you to own or like them, but if you think there is something wrong with others owning them, I feel that is closed minded and hypocritical. This morph has been doing great in the ball python world since 1999

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I mean, I think it depends on what you're planning on using it for. If you're planning on making a web page with morph writeups that is heavily colored by your own opinions -- a bit more like Ralph Davis's site -- then that's fine, and frankly you can do whatever you want ... Heck, you can say whatever you want no matter what you're using it for, but IMO if you're looking to create an impersonal database of morph knowledge, I wouldn't put anything terribly opinionated.

I guess the thing is, I really don't see how it's hypocritical for someone to disapprove of breeding spiders (unless the person also bred, say, fainting goats or neuro Enigma leopard geckos -- then it WOULD be the definition of hypocritical!). Closed-minded, maybe, though I don't think it's that, either ...

Also, the terms dominant and recessive DO refer to phenotypes. NOT genotypes. That's a common misconception. Therefore, it is perfectly possible for one given phenotypic manifestation of a gene to be dominant while another is recessive. And if you don't believe me, it is even on Wikipedia, the Source of All Knowledge of Everything (okay not really but it IS on Wikipedia):

http://en.wikipedia.org/wiki/Dominan...is_dominant.3F

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Originally Posted by jjmitchell

as far as no homozygous form existing.... It is a gene that affects an allele with locusts..... just like everything else.... To think that there is no way for an animal to inherit a gene from both parents is ridiculous...... I dont know if the homozygous form is lethal, I personally dont think any of us do... The woma gene is homozygous lethal we see the offspring fail to thrive.... There are a million threads on homozygous lethal spider and the only conclusion we ever seem to come up with is simply we dont know.... As far as recessive lethal we would not see the spider pattern show in a heterozygous animal if the gene was recessive.

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You obviously don't understand a word I said. The gene is recessive for lethality, but dominant in nature when the animal lives.

Recessive means that the trait needs both alleles to exist. In this case, the trait of lethality is recessive because it only happens with both alleles. The spider coloration itself is not recessive, but is associated with the lethality when both alleles are present.

For example, the normal gene becomes a recessive gene when paired with the spider gene because the spider gene acts dominant. Genes can change from dominant to recessive in the presence of other dominant genes.

The day you can breed and prove a homozygous spider, you will disprove the idea of recessive lethality for that gene. Pinstripes were also thought to be like this but Brian at BHB claims to have a homozygous pinstripe, so we'll have to wait and see if that proves out. (You really need 4-5 generations of clutches with all pinstripe offspring to convince.)

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Originally Posted by OhhWatALoser

doesn't mean its recessive, in fact, if thats the case it would be co-dom. Recessive means the heterozygous form does not show, which it obviously does, the spider we all have in our collections.

co-dom means the heterozygous and homozygous form are different. which if it was lethal, het would be spider and homozygous would be dead. still homozygous lethal anyways. the "XX" means homozygous, has nothing to do with recessive, co-dom, or dom.

Way I see it, it doesn't change the odds, sure it changes the ratio of things that actually come out of eggs, but as far as follicles go you still have the 1:2:1 ratio.

That's assuming its even homozygous lethal which there is next to nothing that suggests this lol.



There nothing that suggests that anything would happen to the eggs

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You didn't understand what I said either. Read what I wrote above.

Also there are a lot of other types of genes that have the heterozygous and homozygous form as different traits. I'm not going to teach you all of them, you can go take a class on genetics for that.

I'm trying to understand what you're saying, but it's really confusing.

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co-dom means the heterozygous and homozygous form are different. which if it was lethal, het would be spider and homozygous would be dead. still homozygous lethal anyways. the "XX" means homozygous, has nothing to do with recessive, co-dom, or dom.

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I even got out my genetics notes for you.
Codominance means that both traits are present in the F1 generation but only one shows. A lot of ball python genes are actually Incomplete Dominant because when they are bred with another morph gene, they create a new mixture of the two.
We tend to use codominace for all of the traits, which is fine for layman terms most of the time but is incorrect for what you're saying.

It is lethal only in a homozygous dominant individual which makes the gene for lethality recessive, but the spider trait itself seems dominant in a heterozygous individual. If the homozygous individual was not lethal, then it would probably look the same since the gene acts dominant; but we don't actually know if it would show a codominant different trait since it's never been achieved.

Quote:

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Originally Posted by Serpent_Nirvana

Also, the terms dominant and recessive DO refer to phenotypes. NOT genotypes. That's a common misconception. Therefore, it is perfectly possible for one given phenotypic manifestation of a gene to be dominant while another is recessive. And if you don't believe me, it is even on Wikipedia, the Source of All Knowledge of Everything (okay not really but it IS on Wikipedia):

http://en.wikipedia.org/wiki/Dominan...is_dominant.3F

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this is right off the link you posted

"It is critical to understand that dominance is a genotypic relationship between alleles, as manifested in the phenotype. It is unrelated to the nature of the phenotype itself"

blackcrystal22

I donno what to tell you everything you are saying seem to conflict 100% with anything i have read on this site or anything to do with genetics on the web. even seem to conflict with the wiki link posted, so i donno what to tell you.

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Originally Posted by OhhWatALoser

blackcrystal22

I donno what to tell you everything you are saying seem to conflict 100% with anything i have read on this site or anything to do with genetics on the web. even seem to conflict with the wiki link posted, so i donno what to tell you.

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Then take a genetics class.

Things are very simplified on the web. I don't know why I try to tell you these things that is beyond your comprehension.

But the original post says the gene is "simple dominant" which is incorrect. There is no simple dominant. There are multiple types of dominance and it's never just that simple.

I still stand on that the spider gene is recessive lethality. But here's some 'web' stuff you can read. Since everyone seems to be linking wikipedia:
http://en.wikipedia.org/wiki/Lethal_alleles

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If the mutation is caused by a recessive lethal allele, the homozygote for the allele will have the lethal phenotype.

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http://www.microbiologyprocedure.com...al-alleles.htm
There is more on that website about some other types of inheritance.

Until someone proves otherwise by proving there is a homozygous spider, this is likely the case.

just to clear things up a bit, recessive lethal can be and is the same as homozygous lethal. so basically he is arguing that spiders are homozygous lethal

Quote:

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Originally Posted by blackcrystal22

Then take a genetics class.

Things are very simplified on the web. I don't know why I try to tell you these things that is beyond your comprehension.

But the original post says the gene is "simple dominant" which is incorrect. There is no simple dominant. There are multiple types of dominance and it's never just that simple.

I still stand on that the spider gene is recessive lethality. But here's some 'web' stuff you can read. Since everyone seems to be linking wikipedia:
http://en.wikipedia.org/wiki/Lethal_alleles


http://www.microbiologyprocedure.com...al-alleles.htm
There is more on that website about some other types of inheritance.

Until someone proves otherwise by proving there is a homozygous spider, this is likely the case.

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ok mr college educated, if you going to talk down on me, then put it in stupid for me.

what is the pinstripe and congo then?
do you have any evidence besides "its about time" of a lethal trait present to claim that this is likely?
What other dominant genes also have recessive lethality?
why do the 2 wiki links contradict each other? (this is rhetorical i already know why)

Sorry I have attempted to do some research and so far nothing as conflicted with genes being classified by the gene itself, it is even stated in one of the wiki links posted above as i pointed out. classifying by phenotype to me is makes no sense because obvious 1 gene can effect multiple phenotypes. If there is bad information literally everywhere, does that make me stupid? highly doubt this is beyond my comprehension. There is alot of holes I need filled in tho.

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Originally Posted by blackcrystal22

I even got out my genetics notes for you.
Codominance means that both traits are present in the F1 generation but only one shows. A lot of ball python genes are actually Incomplete Dominant because when they are bred with another morph gene, they create a new mixture of the two.
We tend to use codominace for all of the traits, which is fine for layman terms most of the time but is incorrect for what you're saying.

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If only every one could know this and use it. The terms we use are so inaccurate.

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Originally Posted by OhhWatALoser

What other dominant genes also have recessive lethality?

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The jaguar trait in carpet pythons.

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Originally Posted by TessadasExotics

If only every one could know this and use it. The terms we use are so inaccurate.

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100% agreed.

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Originally Posted by mainbutter

The jaguar trait in carpet pythons.

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co-dom to the rest of us?

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Originally Posted by OhhWatALoser

this is right off the link you posted

"It is critical to understand that dominance is a genotypic relationship between alleles, as manifested in the phenotype. It is unrelated to the nature of the phenotype itself"

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You're misunderstanding what that line means.

The line that you underlined was intended to clear up a completely different common misconception, which is that dominance is a function of the phenotype. Meaning, many people think that a more "intense" phenotype will dominate over a less "intense" phenotype. For example, some people might think that red is dominant to white because red is darker. I really don't know how to explain it better than that because it's an incorrect misconception, but that is what the author is driving at.

You ignored the first line of the Wiki article (emphasis added):

"Rather, the terms simply refer to the visible trait, the phenotype, seen in a heterozygote."

That is in the second line of the paragraph I linked to.

The fact of the matter is, though, that these terms are way too simple to adequately describe genetics as we now understand it. That's why geneticists keep expanding and adding new concepts, such as recessive lethality, and that's why it's such a pain to try and fit these complex genetic concepts into these overly-simplified categories.

I had one genetics professor who hated these terms (dominant, recessive, etc.) for that very reason.

good job on the write-up. :gj: as for the rest of this thread, it just makes my head hurt. lol

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Originally Posted by blackcrystal22

I even got out my genetics notes for you.
Codominance means that both traits are present in the F1 generation but only one shows.

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I'm a little confused by this. Every genetics class I've ever taken, co-dominance is defined as both traits being present in the F1 generation, meaning that both are phenotypically expressed in full. (As opposed to a "blending" as happens in incomplete dom, like you said.)

What you've typed doesn't actually make sense to me ... If both traits are present (the word "trait" suggesting phenotype, not genotype), then wouldn't that be the same as saying that both "show?" :confused:

I need to take a genetics class...:( All this pheno whoknow idontknow stuff is hard to follow. So, recessive lethal. How do you prove that? Would it be just the fact of no super spider existing?

The only thing I don't get with the whole leathal theory is why are there not a lot of bad eggs with spider x spider pairings? I am sure NERD has done tons of Spider combo x spider combo clutches by now to make some of the crazy combos he makes. Unless he is just not reporting any egg death issues I don't see how this theory can hold up. The egg would not get the second spider gene until ovulation. That would mean something would have to come out of the female. Either a bad egg, or a good egg that goes bad during incubation. The point is that there would be evidence of an issue. So far I have not heard of a single person with proof of any leathality issues. The whole thing started from one persons conjecture and that is all it takes in this hobby. Same thing with the caramel females can't lay eggs thing.

Well I didnt mean to call you out lol, I was just under that impression so I double checked everything. Those errors were common little nothings that no one would noticed regularly.

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Originally Posted by LotsaBalls

I need to take a genetics class...:( All this pheno whoknow idontknow stuff is hard to follow. So, recessive lethal. How do you prove that? Would it be just the fact of no super spider existing?

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Taking biology classes is a wonderful idea! I highly encourage it for anyone in the hobby. Heck you don't even really need a class. Wikipedia (longer articles with plenty of references are best) and textbooks get you quite a ways on your own.

As far as proving recessive lethality.. with the jaguar trait in carpet pythons, it's easy. Hatchlings don't fully develop in the egg, and they die off before melanin production occurs. You get all-white baby snakes, dead in their eggs, that ALMOST go full term. It's worked out to be about on average 1/4 of a clutch is dead white snakes from a jag x jag breeding, so it's been inferred that the jaguar trait is homozygous-lethal.

There is less evidence of recessive lethality in spider ball pythons, but there are "guesses". The only real evidence that we have is that there SHOULD have been a homozygous spider produced if it was capable of being produced. On top of that, while we don't understand the exact relation between the presence of the spider trait and the neurological defects known as the "spider wobble", it really wouldn't surprise me that a relation between those defects and homozygous lethality exists.

While there are plenty of holes in the theory that the spider trait is homozygous-lethal (mostly due to lack of concrete evidence, which in itself is a pretty big hole), the lack of a homozygous spider existing poses some serious questions.

We're going to see this issue brought up in the next couple years a bit more I think. With the strong influx of large numbers of bumblebees, I think it's likely that we will see plenty of bumblebee x (spider combo) pairings in the not too distant future. Maybe we'll get more data and be able to form a theory better backed up by actual evidence rather than a lack of evidence.

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Originally Posted by J.Vandegrift

The only thing I don't get with the whole leathal theory is why are there not a lot of bad eggs with spider x spider pairings? I am sure NERD has done tons of Spider combo x spider combo clutches by now to make some of the crazy combos he makes. Unless he is just not reporting any egg death issues I don't see how this theory can hold up.

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That's the big question isn't it, what does Kevin have to say on this matter?

Anyone who breeds gets some amount of egg-death, so it's quite possible that egg death in spider x spider clutches is underreported, or not seen as an anomaly.

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Originally Posted by mainbutter

As far as proving recessive lethality.. with the jaguar trait in carpet pythons, it's easy. Hatchlings don't fully develop in the egg, and they die off before melanin production occurs. You get all-white baby snakes, dead in their eggs, that ALMOST go full term. It's worked out to be about on average 1/4 of a clutch is dead white snakes from a jag x jag breeding, so it's been inferred that the jaguar trait is homozygous-lethal.

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They hatch alive, then die right after, someone even had one live over night, but passed that day. it was pretty obvious it was the homozygous version of the jag, lucy carpet. carpets give you a bigger clutch size so its easier to see things like this compared to ball pythons also.

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Originally Posted by that_dc5

Well I didnt mean to call you out lol, I was just under that impression so I double checked everything. Those errors were common little nothings that no one would noticed regularly.

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hey no problem it needed to be proof read lol. im no english major (obviously)

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Originally Posted by Serpent_Nirvana

You're misunderstanding what that line means.

The line that you underlined was intended to clear up a completely different common misconception, which is that dominance is a function of the phenotype. Meaning, many people think that a more "intense" phenotype will dominate over a less "intense" phenotype. For example, some people might think that red is dominant to white because red is darker. I really don't know how to explain it better than that because it's an incorrect misconception, but that is what the author is driving at.

You ignored the first line of the Wiki article (emphasis added):

"Rather, the terms simply refer to the visible trait, the phenotype, seen in a heterozygote."

That is in the second line of the paragraph I linked to.

The fact of the matter is, though, that these terms are way too simple to adequately describe genetics as we now understand it. That's why geneticists keep expanding and adding new concepts, such as recessive lethality, and that's why it's such a pain to try and fit these complex genetic concepts into these overly-simplified categories.

I had one genetics professor who hated these terms (dominant, recessive, etc.) for that very reason.

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See no matter how many times i read it over, i still can't see it any other way. i mean point me out where i go wrong

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A dominant trait does not mean "stronger," and recessive does not mean "weaker." Rather, the terms simply refer to the visible trait, the phenotype, seen in a heterozygote.

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I understand this as, I'm going to call the albino gene recessive, because in the het form, i cannot see the phenotype. I don't call a super pastel recessive, i call it co-dom, because it is seen in the het form. The phenotype makes the gene described the way it is. which he says later on in the quote i posted before.

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If there are only two phenotypes, and a heterozygote exhibits one phenotype, by definition the phenotype exhibited by the heterozygote is called "dominant" and the "hidden" phenotype is called "recessive." The key concept of dominance is that the heterozygote is phenotypically identical to one of the two homozygotes. The homozygous trait seen also in the heterozygous individual is called the 'dominant' trait.

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I don't see any argument here

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It is critical to understand that dominance is a genotypic relationship between alleles, as manifested in the phenotype. It is unrelated to the nature of the phenotype itself.

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See i don't see anything about misconception, it is only stating how i already think

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, e.g., whether it is regarded as 'normal or abnormal,' 'standard or nonstandard,' 'healthy or diseased,' 'stronger or weaker,' or 'more or less' extreme. It is also important to distinguish between the 'round' gene locus, the 'round' allele at that locus, and the 'round' phenotype it produces. It is inaccurate to say that 'the round gene dominates the wrinkled gene' or that 'round peas dominate wrinkled peas.'

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Now we call them genes in the the reptile world, but would wouldn't lesser be one allele make a heterozygous, and a BEL have 2x lesser alleles.

If this is incorrect then what does the the previous statement mean and what exactly is the difference between the gene locus and allele. because I thought where the alleles physical hung out was called the locus, and the alleles were what we think of as morphs.

... Is it possible that the spider gene simply can't have a super? If Xx is the only kind of spider that will exist? Is there some way of a gene requiring there to be one of each (spider and normal ie: big X and a little x?) aside from recessive lethality? I'm not much of a genetics expert, so I'm not sure if that is a dumb question :D