normal ball + norml ball = albino (is this possible?)

is it possible to breed two normal non het ball pythons and get an albino or some other morph. :confused:

lemme look more into this but

if both have a recessive trait for albino the offspring should have a dominant albino trait

if you breed two "normal" balls together and get an albino then that means that they were "het" for albino all a long.

okay. yeah ill give a bit more detail on this. if you wish to get albino from non albino both must have a recessive trait for albino then 1/4 will be dom trait albino. if just one has the recessive trait it will be passed down to half but it would not be a pheno. they can however pass it down as a dom trait (i belive) to their offspring so 3rd gen some will be albinos.

the only other possible solution i could see coming from 2 normal balls with no recessive albino traits is if a natural mutation actualy happened which is not a frequent occourance

I highly recommend reading up on the genetics of ball pythons. A good starting page is at NERD's website: http://www.newenglandreptile.com/gen...recessive.html.

But to clear up a few points mad in Lokua's post:

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then 1/4 will be dom trait albino

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Actually, it's a little more complicated than that. When you breed a heterozygous to a heterozygous each egg has a 25% chance of being homozygous albino (dom, or dominant, is an entirely different conversation). So often times, the odds don't always add up. There are times when you may end up with 75% of your offspring being homozygous, and there are times when you may end up with 0% of your offspring being homozygous. It's incredibly variable... the statistical values only give us what "we could expect if the world were perfect" ;).

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they can however pass it down as a dom trait (i belive) to their offspring so 3rd gen some will be albinos.

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That's not quite correct. If you breed het to het (of the same trait) each offspring has a 25% possibility of being visiual (homozygous) albino, 50% possibility of being heterozygous albino, and a 25% chance of being entirely normal.

So the only way any of the third generation are coming out albino, is if the breeing pair of second generation carry the albino allele.

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the only other possible solution i could see coming from 2 normal balls with no recessive albino traits is if a natural mutation actualy happened which is not a frequent occourance

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I'm not aware of anyone producing a true De novo mutation in ball pythons. And the likelyhood of producing a de novo albino borders on the extremes of unlikelyhood.

i understand i am new on these fourms and do not wish to step on any toes, nor have i ever bred snakes.

however i have bred plants and also an ADN. in all aspects of encountering the words homozygous and hetrozygous they pertain to parents and the traits passed to children, not if the trait is visible or not. i have read several articles on breeding and all websites list there snakes using hetrozygous so if someone can please clarify these terms for me (as IMHO i do not belive they are the correct terms to be using and unsure why everyone uses them)

in my understanding hetrozygous is when two diffrent traits are passed to the child, example if the snakes mother was albino and father was not then the child would be hetrozygous for albino but that does not state if the child(or hatchling or whatever term you like) will show the albino trait or not, they could receive eather

contray homozygous being two of the same traits from the mother and father being passed to child. thus if the father and mother were both homozygous then that child would have the same trait as the parents, if albino is the visible trait in parents then it would be the same in children.

however saying pairing a hetrozyous with another hetrozygous confuses me. as the two together would be homozygous in there genes to the child as hetro means opposite.

i understand dominant traits (visible) and recessive (underlining) and phenotype, genotype as visible and underling respectfully but really unsure how hetro and homozygous plays into all this

again this is not to start any internet wars or anything, nor attempting to speak outside of my knowledge bank. just stating my opinion and seeking clarification


also on the aspect of produciing a de novo mutation, yes that is extremly rare. why i posted it would not be a frequent occourance. but at one time no mutations existed. highly unlikely but is possible. not something i would suggest looking forward to happening though :)

Lokua,

Justin has it right. I would highly recommend that you follow the link he provided and read up on how the traits are passed.

Heterozygous/homozygous refers to whether the animal is carrying a single gene or matched genes for a particular trait. A heterozygous albino carries a single gene for albino. Since albino is a recessive trait, the animal will appear normal. Its offspring have a 50/50 chance of receiving either the albino gene or the normal gene. If bred to another het albino, the offspring have a 50/50 chance of getting the albino gene from the mother, and a 50/50 chance of receiving the albino gene from the father. IF the offspring receives the albino gene from BOTH parents, it is homozygous, and will display the recessive trait (albino). IF it receives the gene from only one parent, it is heterozygous and will NOT display the recessive trait. It is possible that it won't receive the albino gene from either parent, and will simply be a normal. The odds are - 25% homozygous, 25% normal, and 50% heterozygous. (The passing of the genes and the odds apply to dominant and co-dominant as well, but will be displayed differently.)

Recessive/dominant/co-dominant are all terms that describe how a particular gene is displayed with respect to whether the animal is heterozygous or homozygous. I already talked about recessive. With a dominant trait, the gene is displayed in the same way whether it is heterozygous or homozygous. With co-dominant, a heterozygous animal will display the trait, but a homozygous animal will display it differently, usually more intensely. With the exception of co-dominant, all of this is true whether you're talking about ball pythons, or any other creature. In ball pythons, co-dominant, incomplete dominance, and possibly a few others are generally lumped together into co-dominant (among breeders).

Steve

Here's another really good link to understanding the three various types of genetics that ball python breeders work with (recessive, co-dominant and dominant). It's just a basic idea of it but a great link to start with and work up to NERD's amazing work on genetics and the use of the punnet square.

http://www.ballpython.ca/genetics.html

I remember doing the punnet squares with plants years ago...the concept is the same.

Lokua, the terms used for discussing genetics for all plants and animals are the same, but that doesn't mean everyone understands them and uses them correctly. Steve mentioned that BP breeders have basically lumped co-dom and incomplete dominance together. To be honest, I don't understand the difference between co-dom and incomplete dom enough to be sure if this is true or not, but it gives an example of how in some circumstances some people might use terms incorrectly as long as it works good enough for their purposes.

I think I see where some of your confusion is coming from and I'll try to clarify some of it for you.

Heterozygous and homozygous refer to genes that a certain individual has. Specifically, heterozygous means the individual has 2 different genes at a certain locus, and homozygous means it has 2 genes that are the same. It has nothing to do with the parents, although that is often a really good way to figure out what genes an individual has. However, as you already pointed out in this thread, while extremely rare, it is possible for the freak mutation to occur. In practice, that occurs so rarely that it is safe to assume an individual carries the genes one would expect it to have received from its parents, so it is talked about that way a lot. Of course we don't always know exactly which genes a parent has or which one got passed on, but more on that later. For the rest of this post, I'm going to be assuming that no mutations occur. But even though I'll be talking that way, the fact is that the actual meaning of the words heterozygous and homozygous has nothing to do with the mother or the father or the pairing or any of that.

They also do not mean if a trait is visible or not. However, as long as you know whether the trait in question is recessive, dominant, or co-dominant, you will know what the visual appearance of the snake will be based on knowing if it is het or homo. A recessive trait will only be visible if the individual is homozygous for that trait. So in practice, saying a BP is homozygous for albino also means that snake is a visible albino, and saying a BP is het for albino also means that snake is not a visible albino. And a dominant trait will be visible if the individual is het and also if it is homozygous. A co-dom trait will be visible in both cases, but with a different appearance for het and homo.

In the example you gave, the mother was albino (visible albino, which means homo), the father was not. Unless you know whether the father is het for albino, you can't be sure of the genetics of the offspring. I'll start off assuming the father does not carry the albino gene (this would be homo normal). In this case, you are correct that the offspring would be het for albino, but I think the reasoning you used to get there was wrong, and sometimes having the right answer for the wrong reason can be the worst thing because it makes you think your reasoning was correct and leads to more confusion down the road. You are also right that this doesn't state whether the hatchling will be visible albino. What states that is the knowledge that the albino gene is recessive so it will never be visible unless the individual is homo for it. But again, in practice, it gets cumbersome to say "and since we know albino is recessive" all the time so that phrase gets left out when people talk about breeding an albino to a normal and getting het but not visual offspring.

You say the child could receive either, I believe meaning either the albino gene or the normal gene. This is incorrect. In this example, the child will receive BOTH. The mother has 2 albino genes, and she will pass on one to each of her offspring. The father has 2 normal genes, and he will pass on one to each of his offspring. So the offspring will have one of each, which is what het means, 2 different genes.

If you meant the child could either be a visible albino, or not visible, that is also incorrect, but for a different reason. Albino is a recessive gene, which means it will always be visible when the individual is homo albino, and will never be visible when the individual is het for albino. If we go back and change the example to an albino mother, and instead of a homo normal father we use a het for albino as the father, then you don't know if an individual offspring will be visible or not. The father has 2 different genes, and he will pass on one to each of his offspring, but you don't know which one will end up in which egg. You can expect to get roughly 50% visible albinos and 50% visible normals which are het for albino. You know you won't get any normals that don't carry the albino gene at all because the mother has to pass on one gene, and both of hers are albino. The odds rarely work out exactly, and it is possible even when you "expect" to get 50/50, to get all of one or all of the other.

You said pairing a het with a het confuses you because they are the same and so that should be homo. Well, sort of. Homo is a prefix that means "the same". Homozygous is a word that means an individual has 2 of the same genes at a certain locus. Two individuals can't be homozygous to each other even though they can be the same as each other. The words homozygous and heterozygous only talk about genes in an individual. The words mean nothing about the parents or offspring or anything you might pair up with that individual to breed. However, you can use the information to make a lot of conclusions about the parents, offspring, and what you'd like to breed with the individual to get the offspring you want.

You say you understand dominant and recessive, but also call them visible and underlying, which tells me you probably don't understand them. This is actually a common misunderstanding. Dominant does not mean visible, nor does it mean the gene is more likely to get passed on to the offspring (another common misunderstanding). Dominant means that the gene will be expressed (visible) if it is present in the individual, regardless of whether the individual carries 1 copy (het) or 2 copies of it (homo). Recessive means that the gene will only be expressed (visible) if the individual carries 2 copies of it (homo). This does mean that a dominant trait will always be visible in an individual that carries that gene at all, and a recessive trait has a chance of being underlying in an individual that does not show that trait.

You talk about getting an albino from parents that are both non-albino, and so they'd need to both have the recessive trait for albino. You also said that 1/4 of the offspring would be albino. This actually shows more understanding of how genetics and punnett squares work than a lot of people have, so it is possible that part of what you say that seems like you don't understand is just that you have worded things awkwardly. However, in the same sentence, you say that those offspring will have the dominant trait albino, which is wrong. They will have the visual trait albino, but that doesn't make it dominant. In BPs, albino is recessive. Always. Even when it is visual it is not dominant. It is just that when it is visual, that means both genes at that locus are the albino gene, so there is no room left for a dominant gene, so the recessive one becomes visible.

Phenotype does mean the visible trait an individual shows. Thus, "normal" is the phenotype of both a BP that carries 2 wild type genes, as well as one that is het for albino.

Genotype is what genes an individual actually carries, regardless of whether or not they are visible. so the 2 BPs above have the same phenotype "normal", but different genotypes with one being homo normal and the other being het for albino.

Well, this got really long but I hope it does help clear things up for you.

thanks guys. yeah i got her at a local pet store and they didnt have any info on her genetics. is there some sort of test that a vet could give her on her genetics? any ways ime gonna try some breeding with my friends bp in the next couple of years so lets cross our fingers. Ps. when i got her she was only $75 and at the other pet stores ball pythons that are het are along the lines of something like $150-250. so im doubting shes het but im praying she is.

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Originally Posted by kc261

Steve mentioned that BP breeders have basically lumped co-dom and incomplete dominance together. To be honest, I don't understand the difference between co-dom and incomplete dom enough to be sure if this is true or not.

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It is true, but they are very similar.

An incomplete dominant animal is one that partially expresses a certain phenotype. Let's assume the B* allele is incomplete dominant. If we breed two BB*, the resulting offspring options are BB, B*B* and BB* (or B*B).

Assuming the B allele makes a blue pigment, the BB animal will have dark blue pigment, the B*B* animal will have no blue pigment, and the BB* will have a lighter shade of blue.

The key to understanding the difference is in phenotypes. In incomplete dominance, the dominant allele is the only one expressed, but it's only partially expressed in heterozygous form. In co-dominant mutations, both the wild-type AND the co-dominant allele are expressed in heterozygous form.

This commonly occurs in flowers; pink flowers are often incomplete dominant for the red allele, although that's not always the case.

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Originally Posted by pythontricker

thanks guys. yeah i got her at a local pet store and they didnt have any info on her genetics. is there some sort of test that a vet could give her on her genetics?

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No. When a genetic test is done on a human, the sample is taken and tested against certain genes and chromosomes specific to the (usually) disease a person may have. For example, Huntington's disease, is traceable to one single gene (Htt). There are approximately 20,000 to 30,000 genes in the human body. That should give you a perspective on the odds of finding a specific genetic mutation randomly, especially in a ball python, given that very little genetic research has been done on them.

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Originally Posted by pythontricker

is there some sort of test that a vet could give her on her genetics?

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There is a thread about this right now.
http://www.ball-pythons.net/forums/s...ad.php?t=54943

Since you got her from a pet store, there is no way to know what she is. She could be het for something and the people who sold her to the pet store just didn't bother to pass along that information. Especially if she only had a low chance of being het, that is likely that info wouldn't be passed on to the pet store.

It is also possible she is CH or WC. If so, who knows what genetics she has. She might even carry something new that no one has seen before (extremely unlikely but possible).

The biggest problem is you have no idea what she'd be het for even if she is het for something. So if/when you breed her, you'll have to decide if it is worth it to breed her offspring back to her to try to prove something out, and how many years you'll devote to that. Even if she is het, her offspring will only have a 50% chance of het, so you'd have to breed at least 2 different sons back to her before you'd even be close to being confident she doesn't carry something.

In the meantime, you could be breeding her to a pastel or other co-dom and getting 50% morph babies each year. Or a super pastel or other super and get 100% morph babies each year.

I guess you can kind of do both at the same time by breeding her to a super something the first time, then each year after her babies get big enough, breed her to a different one of her sons and you'll still be getting 50% morphs out of her. But you'll also be inbreeding (or line breeding I guess technically) which should be avoided when possible, for an extremely small chance that she carries something.

Most people would say if you want to breed for morphs, buy snakes that you know carry the gene or at least a high % chance of being het. But there have been 2 stories on bp.net this year of people who hatched out totally unexpected morphs, so it does happen.

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Originally Posted by jhall1468

An incomplete dominant animal is one that partially expresses a certain phenotype. Let's assume the B* allele is incomplete dominant. If we breed two BB*, the resulting offspring options are BB, B*B* and BB* (or B*B).

Assuming the B allele makes a blue pigment, the BB animal will have dark blue pigment, the B*B* animal will have no blue pigment, and the BB* will have a lighter shade of blue.

The key to understanding the difference is in phenotypes. In incomplete dominance, the dominant allele is the only one expressed, but it's only partially expressed in heterozygous form. In co-dominant mutations, both the wild-type AND the co-dominant allele are expressed in heterozygous form.

This commonly occurs in flowers; pink flowers are often incomplete dominant for the red allele, although that's not always the case.

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Thank you for trying to explain this, but I'm still not sure what the difference is.

You give 2 examples of incomplete dominance which end up sounding basically like mixing paint together. Dark blue, no blue, or light blue in a het. Red, white (I assume?), or pink in a het.

Can you give an example of what co-dominance would be? I very vaguely remember something from junior high biology about roan cattle being a mix of red & white hairs. Would that be co-dom? Instead of each hair being pink? Which would be incomplete dominance?

In that case, is pastel technically incomplete dominance? Going back to the mixing paint idea, it is a little like someone mixed normal BP paint with the bright paint of a super pastel, and you end up with snakes with brighter color but not as bright as the supers. And if it were a true co-dom trait, we'd have spots that look normal and spots that look super pastel on a het version?

I know lots of the "het for white" morphs have lots of flames. So I guess this might be a true co-dom, with spots of white showing through? And if they were incomplete dominant traits, you'd end up with snakes that ended up looking pale or washed out evenly across the whole snake in the het version, possibly looking something like a hypo?

You can produce an albino from normals... except then they wouldn't be normals...

It is possible if the animals that you think are normal are actually het albino. That doesn't happen often though... :)

Justin

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Originally Posted by kc261

Thank you for trying to explain this, but I'm still not sure what the difference is.

You give 2 examples of incomplete dominance which end up sounding basically like mixing paint together. Dark blue, no blue, or light blue in a het. Red, white (I assume?), or pink in a het.

Can you give an example of what co-dominance would be? I very vaguely remember something from junior high biology about roan cattle being a mix of red & white hairs. Would that be co-dom? Instead of each hair being pink? Which would be incomplete dominance?

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My explanation sucked, for starters it wasn't complete, and secondly I actually reversed the definitions of the two. Let's hit this from another stand point. Let's say I breed an all black ball python to an all white ball python (let's assume for the moment, both of these traits are base mutations and neither are recessive).

If the alleles are co-dominant, the resulting ball python would be gray. This is the mixing of paint example that you gave. The proteins being produced by both alleles (in this case, pigment proteins) can only produce at about 50% the rate they should, so you have a total of 100% of the protein being produced.

If the alleles are incomplete dominant, the animal would be black and white. This is because each of the alleles is producing 100% of the protein. So the phenotype is a combination of the two.

The roan cattle is an example of co-dominance (but, just to add confusion to the mix, a roan horse is dominant).

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In that case, is pastel technically incomplete dominance? Going back to the mixing paint idea, it is a little like someone mixed normal BP paint with the bright paint of a super pastel, and you end up with snakes with brighter color but not as bright as the supers. And if it were a true co-dom trait, we'd have spots that look normal and spots that look super pastel on a het version?

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I can see why you would get to that point, because my explanation was really screwed up. But when the "paints mix" is co-dominant, when the paints are both displayed in the phenotype, but never mix, it's incomplete dominance.

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I know lots of the "het for white" morphs have lots of flames. So I guess this might be a true co-dom, with spots of white showing through? And if they were incomplete dominant traits, you'd end up with snakes that ended up looking pale or washed out evenly across the whole snake in the het version, possibly looking something like a hypo?

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Well, you are on the right track (had I not reversed the definitions in the first place you'd be dead right). The amount of the two incomplete dominant traits that show through is variable (and depends much more on environment than genetics).

Think of it as buckets of paint. Every ball python requires two gallons of paint to give a phenotype. If it's co-dominant, we mix the paints together really well and we have our phenotype. In incomplete dominance, we keep the paint seperate, but it's still only two gallons.

I looked some photos of Roan cattle, and I think the book is wrong. According to http://www.braunviehcenter.com/cattl...tics_part2.htm it is incomplete dominance, and that makes more sense given the photos of roan cattle are certainly the incomplete dominant phenotype. I'd guess the book was wrong on horses as well.

jhall

I think you had your explanation of incomplete and codom right the first time.

I can't speak for ball genetics, but can give you examples of human genetics.
Codom traits are traits where two dominant alleles are expressed together. A very good example of this is the ABO blood group. Blood types are controlled by 3 alleles, A, B. and i (being recessive to both A and B creating type O blood when the gene is ii). A person who has both A and B alleles will have type AB blood as both alleles are expressed TOGETHER.

Much like roan cattle, the two colors of hair are both expressed, not blended.

Incomplete dominant traits are traits where you have two dominant alleles at a loci but they are expressed in a blended form in the phenotype (this is sometimes also reffered to as intermediate expression). One example in humans is hair type. Hair is controlled by two alleles one for straight hair and one for curly. Someone who has straight hair is homozygous for straight (2 of the same allele). Someone who has curly hair is homozygous for curly. Now if someone has one straight allele and one curly (being heterozygous), it would present in the phenotype as wavy hair, with neither allele being completely dominant over the other, it would show as a blending of the two.

Another example of this is some flower colors (ie. carnations). If a carnation had one red allele and one white allele it would show as a pink carnation.

:):)

Are you sure you had it backwards the first time? After I posted my reply I was getting kind of excited that maybe I understood it and went and googled it, and based on the pages I looked at, I thought I was understanding which means you had it right the first time. Either that or I'm just lost beyond belief.

Here is a couple of pages that I thought explained it reasonably well:
http://users.adelphia.net/~lubehawk/...!/inccodom.htm
http://www.cod.edu/people/faculty/fancher/Dominance.htm

Some tips (sort of modified from the first page with my own embellishments thrown in) that might help remember which is which:
Co-dominance: co meaning together, like in co-exist. You have a third phenotype, but it isn't really something new, just the 2 traits together, side by side, peacefully. Red & white hairs on a roan cow.
Incomplete dominance: one trait tries to dominate the other but doesn't succeed, so they get in a big fight and end up with both of their guts all smushed together and smeared on the pavement. You have a third phenotype, which is what results when those guts get picked back up off the pavement, where they got totally mixed together. Pink flower.


I also found this page, which is a sort of quiz about genetics.
http://gbn.glenbrook.k12.il.us/acade.../Genetics.html
I didn't go through the whole thing and at least one link was broken, but what I saw looked ok. It had a note on one page that is interesting: "Both incomplete dominance and codominance genetics problems work the same way. The only difference is in the way the cell cellular machinery works out the phenotypic expression." (their typo, not mine)

This is why we can get away with lumping everything together into co-dom (or we could call it incomplete dom, it wouldn't matter). The Punnett square works out the same, the only difference would be the appearance of each phenotype which we just memorize what to expect.

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Originally Posted by Sunny1

jhall

I think you had your explanation of incomplete and codom right the first time.

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Damn I've made a bigger mess of this than I thought :P. You are right, I was right the first time... but I'm going to keep my mouth shut and let someone that knows what there talking about... do the talking:

http://users.adelphia.net/~lubehawk/...!/inccodom.htm

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Originally Posted by kc261

Are you sure you had it backwards the first time? After I posted my reply I was getting kind of excited that maybe I understood it and went and googled it, and based on the pages I looked at, I thought I was understanding which means you had it right the first time. Either that or I'm just lost beyond belief.

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I had it right the first time, but screwed it up when I decided to double check. I did a quick google search, and the first site I came up with (http://www.cccoe.net/genetics/codominant.html) has it backwards... so I lost faith in myself and did a switcheroo :P.

That being said... the term "co-dominant" is pretty much used interchangeably with incomplete dominance in ball pythons. Although, from a scientific standpoint that's clearly erroneous. Given that information, I can't think of a single "real" co-dominant mutation, except perhaps the het BEL's you spoke of. In reality, all of the "co-dominant" mutations are actually incomplete dominant.

But now curiosity has me, so I'm trying to think of a truly co-dominant ball python morph.

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Originally Posted by jhall1468

Damn I've made a bigger mess of this than I thought :P. You are right, I was right the first time... but I'm going to keep my mouth shut and let someone that knows what there talking about... do the talking:

http://users.adelphia.net/~lubehawk/...!/inccodom.htm

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Hey, that's one of the pages I posted! I thought it was pretty good too.

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Originally Posted by jhall1468

I had it right the first time, but screwed it up when I decided to double check. I did a quick google search, and the first site I came up with (http://www.cccoe.net/genetics/codominant.html) has it backwards... so I lost faith in myself and did a switcheroo :P.

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That site is messed up. Kinda sloppy with typos and such too. I emailed the guy (who I think is a 7th grade teacher) and basically said he should be embarrassed because he wouldn't accept that kind of work from his students.

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Originally Posted by jhall1468

That being said... the term "co-dominant" is pretty much used interchangeably with incomplete dominance in ball pythons. Although, from a scientific standpoint that's clearly erroneous. Given that information, I can't think of a single "real" co-dominant mutation, except perhaps the het BEL's you spoke of. In reality, all of the "co-dominant" mutations are actually incomplete dominant.

But now curiosity has me, so I'm trying to think of a truly co-dominant ball python morph.

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I understood that with BPs people are pretty much using co-dom for both. It was most of a mental exercise to learn something new.

We should have a contest to see who can come up with a true co-dom morph first! :)