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ok, based on the posts down below, everybody seems to agree that I was wrong on the genetics of hypo and arabesque. Let me see if I have this right in rephrasing after some researching and talking around.

As I sit here with a copy of "Designer Morphs" book by John Berry for reference, I will try to straighten myself out. Not to bash anybody, but this book has almost everything listed as co-dom, so forgive me for my last post. So anybody please feel free to point me in the right direction if I am wrong.

The definition of Co-dom by this book-
"A snake with two equally dominant traits being expressed. The homozygous form looks different to the heterozygous. In the punnet square, breeding a co-dominant animal to a normal wild type, results in approximately half the young expressing the homozygous trait."

The only problem I have with this definition.... breeding the co-dom (het) form of lets say motley, to a normal wild type, would produce more co-dom (het) motleys, not homozygous (super) motleys as stated in the definition. Is that correct?

Lets make some comparisons/examples. I am personally not a fan of Ball Pythons, but I am going to make a comparison. "Fire Balls," (het for Black eyed Leucistic) have an obviously different appearance to them than a normal ball python (as would a motley boa to a normal boa). They are said to be co-dom. In breeding a "fire" to another "fire", Black Eyed Leucistic is produced, with leucistic being completely different in appearence than the "fire" ball. Therefor, in a litter of both hets and leucistics, you could say DUH thats a Fire, and DUH thats a leucistic.

Now, in comparing this theory to boas, I will use hypos for an example. breeding a hypo x hypo, you would produce both supers and normal hypos, neither of which can be distinguished from eachother. although we can take an educated guess, we dont know until it's proven out.

Next example is the motley x motley. you would produce both supers (solid black with no pattern) and normal motleys, of which you could visibly tell the difference between the 2 because of color/pattern. here we go again, DUH thats a super, DUH thats not!

In conclusion, hypos and arabesques would be dominant as everybody stated, and motleys would be co-dom.

That being said, please belive me that I understand how the genetics behind it all work, I just got the terms confused in my head. I've spent way more than my share of time staring into the computer screen and books reading, and this was just a simple mistake. I apoligize to anybody I may have confused, but hopefully this one hits it on the head and speaks clearly.

Again, if this post is wrong, somebody set me straight, I think too many people have the idea of co-dom meaning that if it is bred to a normal boa, 50% of the litter will be that co-dom snake. Therefor people look at hypos/arabesques/motleys all the same because the results are the same when bred to a normal wild type. But the difference between them is clearly distinguished when breeding a co-dom x co-dom because of the visible differences in the heterozygous and homozygous forms of the genes.

I didn't have time to review all the info. you have presented here. But remember we all had to start somewhere. There are many breeders that started out with that first pet boa, with little understanding about genetics, breeding, local specific differences, etc....

It seems like you were "torn a new one" on that last post, so keep your chin up. We are all learning , and even the best of em' have only scratched the surface of genetics. The more we learn , the more questions we have.

Good luck with you're findings. Sorry I didn't have the time to address or try to clarify some of your questions. I'll leave that to some one who knows more on the subject.

I'm still confused on the hypo genetics. When Rich Ihle states over and over that some of his snakes are probable super hypos because they have a cleaner look... I always think co-dominate based on that statement. I'd assume that Ihle was a well respected breeder of hypos. But every one else seems to think they are dominant or incomplete dominant????

So needless to say I have questions of my own..

We are all on an information quest. Just hang in there.

Chris

in the grey area between dominant and co-dominant. in a hetXhet or hetXhom breeding there will be hets and homozygous animals produced. Some homozygous can be picked out of the "pile" based on appearance. BUT, you can't divide the "pile" into two clear groups, het and homozygous. So by default, since it does not completely "fit" into the co-dom description, it defaults back to dominant.

All major profs to Rich and yes he can pick out "probables", but they are described as "probable supers" not supers. In a true co-dom trait like motley, it's easy to sort the babies into het motley and homozygous/super motley.

>>I didn't have time to review all the info. you have presented here. But remember we all had to start somewhere. There are many breeders that started out with that first pet boa, with little understanding about genetics, breeding, local specific differences, etc....
>>
>>It seems like you were "torn a new one" on that last post, so keep your chin up. We are all learning , and even the best of em' have only scratched the surface of genetics. The more we learn , the more questions we have.
>>
>>Good luck with you're findings. Sorry I didn't have the time to address or try to clarify some of your questions. I'll leave that to some one who knows more on the subject.
>>
>>I'm still confused on the hypo genetics. When Rich Ihle states over and over that some of his snakes are probable super hypos because they have a cleaner look... I always think co-dominate based on that statement. I'd assume that Ihle was a well respected breeder of hypos. But every one else seems to think they are dominant or incomplete dominant????
>>
>>So needless to say I have questions of my own..
>>
>>We are all on an information quest. Just hang in there.
>>
>>Chris
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC)
0.2 kids (CBB, selectively bred from good stock)

LOL, to many snakes to list, last count:
12.24 BRB
11.13 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

I find the link posted in Paul's thread on this topic very interesting. Click on the link he provides and look at the bottom of the chart where he discribes the Synonyms to co-dominance. He says that incomplete dominance or less than dominant is still co-dominant.

Granted , the differences between a het. and hom. hypo. are very subtle compared to a motley or a jungle. But, when Rich uses the word "probable", then it does seem to indicate that differences can be identified with some consistency.

So , maybe the "default" is co-dom rather than dom. in this particular phenotype.

I still disagree and I believe Paul is with me from prior discussions we've had on the subject. The full text from the link Paul gave:

*Codominant is used as a catch-all term for all genetic conditions producing three distinct phenotypes from three combinations of two genes. Synonyms include incomplete dominant, less than dominant, partial dominant, semidominant, transdominant, and others.

Codominant is described as having "three distinct phenotypes" not probably distinct phenotypes.

>>I find the link posted in Paul's thread on this topic very interesting. Click on the link he provides and look at the bottom of the chart where he discribes the Synonyms to co-dominance. He says that incomplete dominance or less than dominant is still co-dominant.
>>
>>
>>Granted , the differences between a het. and hom. hypo. are very subtle compared to a motley or a jungle. But, when Rich uses the word "probable", then it does seem to indicate that differences can be identified with some consistency.
>>
>>
>>So , maybe the "default" is co-dom rather than dom. in this particular phenotype.
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC)
0.2 kids (CBB, selectively bred from good stock)

LOL, to many snakes to list, last count:
12.24 BRB
11.13 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

There are a dozen or so synonyms for "codominant" because a number of people independently discovered mutant genes that did not fit Gregor Mendel's dominant vs. recessive model.

Rich Ihle uses the word "probable". That word is the reason I think salmon is better described as a dominant mutant than a codominant mutant.

Paul Hollander

I have to admit, every time I read paul's explanations I see a articulate well stated point. Then I think to myself "I wish I could have thought of that". So, I'll consider your point.

Good discussion guys,

Chris

see my input below in blue

>>ok, based on the posts down below, everybody seems to agree that I was wrong on the genetics of hypo and arabesque. Let me see if I have this right in rephrasing after some researching and talking around.
>>
>>As I sit here with a copy of "Designer Morphs" book by John Berry for reference, I will try to straighten myself out. Not to bash anybody, but this book has almost everything listed as co-dom, so forgive me for my last post. So anybody please feel free to point me in the right direction if I am wrong.
>>
>>The definition of Co-dom by this book-
>>"A snake with two equally dominant traits being expressed. The homozygous form looks different to the heterozygous. In the punnet square, breeding a co-dominant animal to a normal wild type, results in approximately half the young expressing the homozygous trait."
>>
>>The only problem I have with this definition.... breeding the co-dom (het) form of lets say motley, to a normal wild type, would produce more co-dom (het) motleys, not homozygous (super) motleys as stated in the definition. Is that correct?
>>
I agree with your analysis and would take it a step further. STOP describing the individual animal as co-dom or dom, rather describe as het or homozygous for the co-dom or dom trait. For example a het motley or a homozygous salmon.

>>Lets make some comparisons/examples. I am personally not a fan of Ball Pythons, but I am going to make a comparison. "Fire Balls," (het for Black eyed Leucistic) have an obviously different appearance to them than a normal ball python (as would a motley boa to a normal boa). They are said to be co-dom. In breeding a "fire" to another "fire", Black Eyed Leucistic is produced, with leucistic being completely different in appearence than the "fire" ball. Therefor, in a litter of both hets and leucistics, you could say DUH thats a Fire, and DUH thats a leucistic.
>>
>>Now, in comparing this theory to boas, I will use hypos for an example. breeding a hypo x hypo, you would produce both supers and normal hypos, neither of which can be distinguished from eachother. although we can take an educated guess, we dont know until it's proven out.
>>
>>Next example is the motley x motley. you would produce both supers (solid black with no pattern) and normal motleys, of which you could visibly tell the difference between the 2 because of color/pattern. here we go again, DUH thats a super, DUH thats not!
>>
>>In conclusion, hypos and arabesques would be dominant as everybody stated, and motleys would be co-dom.
>>
I believe that's the consensus but not fully proven out on the arabesque....yet!

>>That being said, please belive me that I understand how the genetics behind it all work, I just got the terms confused in my head. I've spent way more than my share of time staring into the computer screen and books reading, and this was just a simple mistake. I apoligize to anybody I may have confused, but hopefully this one hits it on the head and speaks clearly.
>>
I applaud you in admitting your confusing terms and it does appear you're understanding it and describing it correctly in this post.

>>Again, if this post is wrong, somebody set me straight, I think too many people have the idea of co-dom meaning that if it is bred to a normal boa, 50% of the litter will be that co-dom snake. Therefor people look at hypos/arabesques/motleys all the same because the results are the same when bred to a normal wild type. But the difference between them is clearly distinguished when breeding a co-dom x co-dom because of the visible differences in the heterozygous and homozygous forms of the genes.

Most people seem to grasp the recessive traits fairly easily. It's the Dom and Co-Dom traits that throw them for a loop. Add to that everyone describing an individual animal as dominant or co-dominant in an attempt to describe the specific genes in that animal and no wonder people get confused.
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC)
0.2 kids (CBB, selectively bred from good stock)

LOL, to many snakes to list, last count:
12.24 BRB
11.13 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

I appreciate everybodys support and understanding of my post the other day compared to this last one.

One thing I do want to touch on though, I did mention a little bit in the last post, a lot of people seem to think of co-dom/dominant genes the wrong way. I hear people talk of hypo/motley/arabesque/ect as co-dom because if bred to a normal wild type, 50% of the litter will be the mutant gene and the other 50% would be normal wild type. And they also consider a dominant gene to be the "super" form where the mutant gene is bred to a normal wild type, and 100% of the litter would come out as this mutant gene, or "hets" if you will. In a way, that is correct by using the "super" to get those results, but it's... how do I say.... thinking along the wrong path???? I don't know how to explain that co-dom/dominant is not determined by the % or outcome of the mutant gene in a litter, but rather based on comparing the homozygous mutant gene to the same form of a heterozygous mutant gene.

Is it safe to say that a way to successfully determine a co-dominant gene to a dominant gene would be to look at the phenotype of the homozygous form of the mutant gene? After all, that seems to be what it is based on, is whether or not the "super" (homozygous) form of the gene is a noticeably different phenotype than the heterozygous form of the same gene.

I guess looking at that perspective, I could see how hypomelanistic would be in a grey area because of the idea of "possible" supers based on black reduction and/or color/pattern.

Some food for thought-
I've heard people say Hypos are an incomplete form of albino because of the reduction in melanin. Is there more to be said about this or is it just an opinion? It seems like something is missing to that puzzle, maybe I just haven't caught it yet.

dom and co-dom are NOT the correct terms to describe the qty of mutant genes a specific animal has. They are to describe the relationship between the mutant genes and the expression of the trait. No different than recessive.

Heterozygous and homozygous ARE the correct terms to describe the genes in an associated gene pair.

>>I appreciate everybodys support and understanding of my post the other day compared to this last one.
>>
>>One thing I do want to touch on though, I did mention a little bit in the last post, a lot of people seem to think of co-dom/dominant genes the wrong way. I hear people talk of hypo/motley/arabesque/ect as co-dom because if bred to a normal wild type, 50% of the litter will be the mutant gene and the other 50% would be normal wild type. And they also consider a dominant gene to be the "super" form where the mutant gene is bred to a normal wild type, and 100% of the litter would come out as this mutant gene, or "hets" if you will. In a way, that is correct by using the "super" to get those results, but it's... how do I say.... thinking along the wrong path???? I don't know how to explain that co-dom/dominant is not determined by the % or outcome of the mutant gene in a litter, but rather based on comparing the homozygous mutant gene to the same form of a heterozygous mutant gene.
>>
>>Is it safe to say that a way to successfully determine a co-dominant gene to a dominant gene would be to look at the phenotype of the homozygous form of the mutant gene? After all, that seems to be what it is based on, is whether or not the "super" (homozygous) form of the gene is a noticeably different phenotype than the heterozygous form of the same gene.
>>
>>I guess looking at that perspective, I could see how hypomelanistic would be in a grey area because of the idea of "possible" supers based on black reduction and/or color/pattern.
>>
>>Some food for thought-
>>I've heard people say Hypos are an incomplete form of albino because of the reduction in melanin. Is there more to be said about this or is it just an opinion? It seems like something is missing to that puzzle, maybe I just haven't caught it yet.
-----
Thanks,

Dave Colling

www.rainbows-r-us-reptiles.com

0.1 Wife (WC)
0.2 kids (CBB, selectively bred from good stock)

LOL, to many snakes to list, last count:
12.24 BRB
11.13 BCI
And those are only the breeders

lots.lots.lots feeder mice and rats

>I don't know how to explain that co-dom/dominant is not determined by the % or outcome of the mutant gene in a litter, but rather based on comparing the homozygous mutant gene to the same form of a heterozygous mutant gene.

The link below may help.

>I've heard people say Hypos are an incomplete form of albino because of the reduction in melanin. Is there more to be said about this or is it just an opinion? It seems like something is missing to that puzzle, maybe I just haven't caught it yet.

It's based on a wide definition of the word "albino". The actual biochemistry of the two mutants is unknown, unfortunately. But the biochemical action of the two mutants is probably quite different. Here's an analogy. Acute bronchitis and lung cancer similar in that both are respiratory ailments. But they are very different in many ways. Salmon (AKA hypo) and albino are also different in many ways.

Paul Hollander

Comparison of dominant, codominant, and recessive.

Spank me that man is good!
-----
1.0 ghost
1.1 albino
0.1 het albino

>As I sit here with a copy of "Designer Morphs" book by John Berry for reference, (snip)
>
>The definition of Co-dom by this book-
"A snake with two equally dominant traits being expressed. The homozygous form looks different to the heterozygous. In the punnet square, breeding a co-dominant animal to a normal wild type, results in approximately half the young expressing the homozygous trait."

That is a pretty sad definition. First, "codominant" does not refer to the snake, it refers to the mutant gene.

Here is a better definition:

Codominant mutant gene -- A mutant gene is codominant to the wild-type (or normal) version of the gene if it satisfies both of the following two criteria:
1. A snake that has a pair of the mutant genes does not look like a snake with a pair of the wild-type genes.
2. A snake that has a mutant gene paired with a wild-type gene does not look like either the snake with two mutant genes or the snake with two wild-type genes.

A gene pair, and the snakes that possess it, can be broken down into seven categories:

1. Homozygous for a wild-type gene. Has two copies of the wild type gene. The snake looks like most of the snakes found in the wild. Such snakes are often called "normal".

2. Homozygous for a mutant gene that is dominant to the wild-type gene. Has two copies of the dominant mutant gene. The snake does not look normal.

3. Heterozygous for a mutant gene that is dominant to the wild-type gene. Has one copy of the dominant mutant gene paired with one copy of the wild-type gene. The snake either looks like or cannot be reliably distinguished from a snake that is homozygous for the mutant gene.

4. Homozygous for a mutant gene that is recessive to the wild-type gene. Has two copies of the recessive mutant gene. The snake does not look normal.

5. Heterozygous for a mutant gene that is recessive to the wild-type gene. Has one copy of the recessive mutant gene paired with one copy of the wild-type gene. The snake looks like one that is homozygous for the wild-type gene.

6. Homozygous for a mutant gene that is codominant to the wild-type gene. Has two copies of the codominant mutant gene. The snake does not look normal.

7. Heterozygous for a mutant gene that is codominant to the wild-type gene. Has one copy of the codominant mutant gene paired with one copy of the wild-type gene. The snake can be reliably distinguished from a snake that is homozygous for the mutant gene and from a snake that is homozygous for the wild-type gene.

>Again, if this post is wrong, somebody set me straight, I think too many people have the idea of co-dom meaning that if it is bred to a normal boa, 50% of the litter will be that co-dom snake. Therefor people look at hypos/arabesques/motleys all the same because the results are the same when bred to a normal wild type. But the difference between them is clearly distinguished when breeding a co-dom x co-dom because of the visible differences in the heterozygous and homozygous forms of the genes.

The definition in Berry's book is pretty poor, but you are on the right track.

Paul Hollander

Much better! It is sad that the information in the book is not accurate.

One thing to add, based on your look at the Motley X Motley, Hypo X Hypo, and Fire X Fire it seems you forgot or didn't know that there are also Normals born from such breedings. Just wanted to clarify that.

Also, it is bad to refer to animals as co-dominant or dominant, they are not. They are heterozygous or homozygous, the mutation they carry is the thing that is co-dom or dom.

Homozygous or Super, and Heterozygous or non-Super are the correct terms. The "super" name is slang, but has valid meaning.

in the other post. It was not meant to be hard on you per say mostly just trying to nip the spread of misinformation in the bud. Glad to see you are studying up on the genetics so you will be able to give correct advice in the future. Good luck Vinnie
-----
Thanks Vinnie Caruso
opinons are like a--holes... everybody has one and they all stink

There is a lot of material printed for reptiles is full of quality information. But, if you REALLY want to learn about genetics, snake books are not the place to do it. Like Vince said, there is a lot of misinformation being spread around. Unfortunatly most editors do not know much about genetics and I would say more incorrect information has been published than corret when it comes to reptiles.

I would highly recommend picking up a quality textbook, like iGenetics, A Moldecular Approach, by Peter Russell. This is the book I have used for upper division genetic classes (pre-med/vet). Lots of details you can get lost in that deal with genetic at a molecular level, but the information is solid. I am sure there are some other great books out there, I am just not very familiar with them (just make sure it is recent because we are learning more daily).

Hope this helps