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someone please go into detail on the difference? as I understand it, Hypo is a dominant gene while motley is said to be co-dom. yet, both produce a "super form." how does this work, and where do arabasques fall in? supposedly arabasques are dominant, anybody proven it out yet?

hypo is co-dominant.
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0.1 Het Albino
1.0 DH-Sunglow

Arabesque ,hypo and motleys are all co-dom,if you breed a pair of the smae together (ie motley to motley )then you will end up with some supers ,these supers then become dominant

I dont believe Arabesques have been proven to produce a dominant animal, or Super Arabesque.

Here is a great link to Genetic information about co-dom and dom traits.

Scroll to the bottom of the page and it has all the genetic links....hope this helps you out.
http://www.newenglandreptile.com/care.html

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Brandon Nixon

Arabesques (or any other mutation) can not produce a dominant animal. Animals are not dominant or co-dominant, the mutation they carry is. Animals are heterozygous or homozygous.

You are right though, in the idea you were trying to get across. Arabesques have not been proven to have a distinct super form, although homozygous Arabesques likely resulted from Steve Hammond's breeding. As a result the mutation is a dominant mutation, since the homozygous and heterozygous forms are alike.

I get what you mean, my wording wasnt correct it was late when I posted lol, I remember reading about the Animals that Steve produced and they looked insane but what came of them have any of them been bred?
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Brandon Nixon

An animal is not co-dominant or dominant, the mutation it has is. According to your post you are classifying Supers (homozygous) as Dominant, which is in fact incorrect.

The Hypo mutation is dominant. Both the heterozygous and homozygous forms have the same phenotype. Better called an incomplete dominant mutation. The Hypo animals are either heterozygous or homozygous (labeled as non-super or super).

Arabesque is a dominant mutation, at this time. There still needs to be more breeding trials to prove this.

Motley is co-dominant. The heterozygous form is the Motley, the homozygous form is Patternless. In slang, the homozygous is the Super form.

Remember Heterozygous simply means that the animal only has ONE gene for the mutation, a matching pair would result in a homozygous animal.

This works for ALL genetic mutations, not just recessives.

The Hypo mutation is dominant. The heterozygous and homozygous forms have the same phenotype.

If there was a distinct phenotype for the super (homozygous) as opposed to the heterozygous (non-super) form, then the mutation could be classified as co-dominant.

Based on the characteristics of the mutation, and how it works, it is best to classify Hypos as incomplete dominant. Incomplete Dominance IS NOT the same as co-dominant.

Motleys are perhaps the best example of a co-dominant mutation in boas.

Forms of dominance: Codominance --- Simple Dominance --- Incomplete Dominance

As has been said, with codominance the heterzygous and homozygous forms (aka, non-"super" and "super" forms) are visually distinguishable ... different phenotypes.

The way I understand it is that incomplete dominance creates a third phenotype that is a blending of the parental traits, ie red flower x white flower = pink flower. Not the case with hypos (you get hypos).

So that rules out both incomplete dominance and codominance.

someone please go into detail on the difference? as I understand it, Hypo is a dominant gene while motley is said to be co-dom. yet, both produce a "super form." how does this work, and where do arabasques fall in? supposedly arabasques are dominant, anybody proven it out yet?
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Take Care,

-Ryan Homsey

www.topnotchboas.com

co-dominant or incomplete dominant?
perhaps this will help, certain traits form a basis for color or pattern (whether black or red pigment is present for example). Other traits "modify" the colors or patterns. Mutations or genetic factors can be dominant, recessive, incompletely dominant, co-dominant...and all or some are modifiers or form basic color/pattern.

The hypo trait modifies the normal pattern as well as the coloration. The extent to which it modifies the snake depends on whether the snake inherits one or two copies of this trait. This is not always the case with other mutations (ie, recessives which require the snake to inherit 2 copies or else the trait does not "appear" at all. polygenetic traits where the color/pattern if very variable and not exactly on/off like in jungle).

The hypo trait appears to lessen the black pigment and restrict the placement of the pigment (ie smaller saddles). If one "gene" or trait for this is recieved, the modification will always be "seen" or phenotypic. It can't be hidden. That's why hypo is referred to as "co-dominant". A hypo will look like a hypo, or else it is not a hypo. It's either there, or it's not. But the trait is not necessarily "Dominant" over another trait. Like Normal is dominant over albino. It's just a modifier.

Color and pattern have all sorts of modifiers. Hypo-melanism isn't the only one. So when people say it's hard to tell a "super hypo" from a "normal hypo" they are probably right. There are also incomplete dominance factors which are Polygenetic, ie, not a sure thing when inherited, variable, all over the place (like high-pink or pastel).

But take a Normal. A normal that is homozygous for normal (AA) looks just the same as the normal that is heterozygous for normal (Aa) and carries a hidden albino gene. That's because the albino gene is a true recessive. and the Normal is a true dominant.

Another comparison. Horses come in 2 colors only. Red or black. Everything else is a modification of these 2 colors. The creme gene modifies red, so a chestnut horse with the creme gene becomes a palomino (golden w/ light mane/tail). Sometimes it's hard to tell a light red horse from a dark palomino horse because there are other factors such as smutty (the addition of black hairs) which can muddy the color. Fortunately in the horse world we have a test for the creme gene (as well as for black and red). So if there is any question, the horse can be genetically tested to determine it's true genetic coloration.

np
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Take Care,

-Ryan Homsey

www.topnotchboas.com

>The hypo trait appears to lessen the black pigment and restrict the placement of the pigment (ie smaller saddles). If one "gene" or trait for this is recieved, the modification will always be "seen" or phenotypic. It can't be hidden. That's why hypo is referred to as "co-dominant".

Sorry. That is why hypo is not referred to as a "recessive". In the broad sense, any mutant gene that is not a recessive mutant could be classed as a dominant mutant. But this does not explain why salmon (hypo) is better classed as a dominant mutant than as a codominant mutant.

>A hypo will look like a hypo, or else it is not a hypo. It's either there, or it's not. But the trait is not necessarily "Dominant" over another trait. Like Normal is dominant over albino. It's just a modifier.

Using "modifier" in this sense, albino is just a modifier, too. Albino modifies the color so that there is no black there.

When I took genetics, "modifier" was a mutant gene that modified the phenotype produced by another mutant gene and could not be detected otherwise. If smutty in horses can be detected by its effect on the palomino phenotype and can't be detected in a wild type horse (bay, I believe), then smutty would be a modifier.

Paul Hollander

It all comes down to phenotypes. If there are three possible phenotypes then it's Codominant.

ie Motley:
Normal = both genes normal
Heterozygous or Motley = one motley gene, one normal gene
Homosygous or Motley-purple patternless = two motley genes

If there are only two then it's Dominant.

ie Salmon:
Normal = both genes normal
Salmon = at least one Salmon gene, could have both genes Salmon

The difference is if you have a pile of babies from a pairing where each parent had a Salmon gene, you cannot reliably sort the babies into het for Salmon and Homozygous for Salmon. Yes, several of the babies can be visually identified as probably het or probably Homozygous but there is too much of a grey area in the middle where the babies are not easily identified. And the probables are just that, not like a motley pairing where duh, that has to be homozygous and duh, that's a het.

Super is a slang term used to describe a snake with a homozygous gene pair. Typically used for Dominant genes where the hets and homozygous animals cennot be reliably sorted.

ie Super Salmon would have two Salmon genes.
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Thanks,

Dave "Rainbows-R-Us"

0.1 Wife (WC)
0.2 kids (CBB)
2.7 Brazilian Rainbow Boa (adult breeders)
2.5 Brazilian Rainbow Boa (sub-adult from 2004)
4.8 Brazilian Rainbow Boa (sub-adult from 2005)
2.1 Hypomelanistic BRB
0.1 Het for Hypomelanistic BRB
0.1 BCI "Elvira" normal from 1989
1.0 BCI Albino / het-anery
0.1 BCI Salmon / het-albino
0.1 BCI Anery / het-albino
0.1 BCI Salmon (possible super)
1.0 BCI Albino het stripe
1.0 BCI Salmon
0.1 BCI Ghost
0.1 BCI Super salmon, possible jungle
1.0 BCI Salmon, possible jungle
0.1 BCI Super Ghost

lots.lots.lots feeder mice and rats

>Forms of dominance: Codominance --- Simple Dominance --- Incomplete Dominance

Actually these are the three forms: dominance (AKA full dominance), codominance (synonyms: incomplete dominance, semidominance, partial dominance, transdominance, less than dominant, etc.), and recessive.

>As has been said, with codominance the heterzygous and homozygous forms (aka, non-"super" and "super" forms) are visually distinguishable ... different phenotypes.

>The way I understand it is that incomplete dominance creates a third phenotype that is a blending of the parental traits, ie red flower x white flower = pink flower.

In other words, red flower is the homozygous normal, white flower is the homozygous mutant (super in herper lingo), and pink flower is the heterozygous form. The heterozygous and homozygous forms are visually distinguishable making this an example of codominance.

I know that the texts often use this flower example as an example of incomplete dominance. In the strictest sense, the difference between a codominant and an incomplete dominant requires data on whether the mutant gene produces a functional product or not. This data is often unavailable. So we have to fall back on a looser definition in which "codominant" and "incomplete dominant" are synonyms.

>Not the case with hypos (you get hypos).

Right.

>So that rules out both incomplete dominance and codominance.

Right.

>someone please go into detail on the difference?
>
>as I understand it, Hypo is a dominant gene while motley is said to be co-dom. yet, both produce a "super form."

I define "super" as herper slang for the homozygous form of both dominant and codominant mutants. There are very few codominant and dominant mutants in snakes so far, and there has been a lot of misuse of standard genetic terms. Even NERD's page isn't 100%. You can delete "super" from your genetics vocabulary without any loss.

>how does this work, and where do arabasques fall in? supposedly arabasques are dominant, anybody proven it out yet?

Sorry, I don't know the answer to that question.

"Hypo" is a synonym for "salmon". There was a recent thread in the boa genetics, morphs, and locality subforum called $64 question on salmon boas where a lot of this was thrashed out. You ought to check it out. Link is below.

Paul Hollander
$64 question on salmon boas

Codominant and incomplete dominance are totally different.

Incomplete dominance shows a mixing of phenotypes of the two genes in the heterozygous form, hence the pink flower from a red and a white.

Codominant shows BOTH phenotypes simultaneously. If the red and white flowers are codominant, you will get red and white petals in the flower as opposed to a mix. If the petals form the same, then you will have white and red flowers on the same plant. Either way, you get both exact phenotypes and not a mix.

This is why dominant boa morphs would be classified as incomplete dominance and not codominance. If patternless were codominant, I dont think there would be a specific pattern on the motley. Heterozygous hypos are a little darker than supers and a little lighter than normals, demonstrating a mixing of the trait. Codominance here would show some hypo scales and some normal black scales on the heterozygous.
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It's just like the story of the grasshopper and the octopus. All year long the grasshopper stored up acorns for winter, while the octopus mooched off his girlfriend and watched tv. And then the winter came, and the grasshopper died, and the octopus stole all his acorns, and he got a race car. Is any of this sinking in?

>Codominant and incomplete dominance are totally different.

Well, they are similar in at least one way. In both, the heterozygous form can be distinguished from the two homozygous forms. And that is why we can use "incomplete dominance" and "codominance" as synonyms. I prefer "codominance" because it takes less typing.

>Incomplete dominance shows a mixing of phenotypes of the two genes in the heterozygous form, hence the pink flower from a red and a white.
>
>Codominant shows BOTH phenotypes simultaneously. If the red and white flowers are codominant, you will get red and white petals in the flower as opposed to a mix. If the petals form the same, then you will have white and red flowers on the same plant. Either way, you get both exact phenotypes and not a mix.

Part of the difficulty is that "codominant" came out of the discovery of A, B, and AB blood types, molecular level testing. "Incomplete dominant" and several other terms came animal and plant breeding, where phenotype was on the organism level as determined by the unaided Mark I eyeball. Molecular level testing is far more sensitive than the eyeball. That's why they can pick up both the A and B phenotypes in AB individuals.

When you get down to the molecular level, it turns out that heterozygous cells produce a mixture of two gene products. One gene product is the same as that made in one parental homozygous form, and the other gene product is the same as that made in the other parental homozygous form. Note that this is within each cell, not one product in one cell and the other product in a totally different cell. The intracellular mixture of products is why you can get an intermediate phenotype on the organism level in both codominance and incomplete dominance.

I'm not denying that there are some differences between incomplete dominance. But from what I've found, it is primarily in functionality and the quantitative effects of the two gene products.

As the molecular genetics boys get their innings, I think there will be some changes in the way some of the standard terms get defined in the texts.

>This is why dominant boa morphs would be classified as incomplete dominance and not codominance. (snip)

This does not compute. Standard operating procedure in genetics is to call a dominant mutant gene a dominant mutant gene. A dominant is neither an incomplete dominant nor a codominant.

Paul Hollander

I realize that both genes are present in each cell, I think that in the cases of codominance the first protein to become transcribed becomes the phenotype, or maybe only one of the genes transcribes, making a 50% chance for either or. A true example is brown and black horse hairs, with the codom showing fully brown and fully black hairs across the body, not uniformly colored hairs. Same with hypo boas, both genes are required for proper pigmentation, missing one gene results in a lighter hypo and lacking both would be even lighter, the super.
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It's just like the story of the grasshopper and the octopus. All year long the grasshopper stored up acorns for winter, while the octopus mooched off his girlfriend and watched tv. And then the winter came, and the grasshopper died, and the octopus stole all his acorns, and he got a race car. Is any of this sinking in?

I have always refered to Hypos as dominant, but I am begining to think that incomplete dominant might be a better label.

When Rich first published his paper he called the mutation incomplete dominant. I am familiar with your analogy with the flower, white X red = pink.

I think that since the Hypos have so much variability within a litter between both heterozygous and homozygous forms, and since they contribute variably when combined with other mutations that the incomplete dominance label is fitting. Obviously in cases such as this, we are left to label the mutation the best way we can, and this is really only done for understanding on a common basis.

What do you think?

>I think that since the Hypos have so much variability within a litter between both heterozygous and homozygous forms, and since they contribute variably when combined with other mutations that the incomplete dominance label is fitting. Obviously in cases such as this, we are left to label the mutation the best way we can, and this is really only done for understanding on a common basis.

The variability when combined with other, independent mutants doesn't really count in the dominant-codominant-recessive classification. Salmon (Hypo) is obviously not a recessive mutant gene. Salmons have so much variability within a litter between heterozygous and homozygous forms that often they cannot be separated. That's why I think that salmon is better classed as a dominant mutant gene than a codominant mutant gene. I know that Rich Ihle called salmon an "incomplete dominant". I'd agree with him only if he can distinguish homozygous salmons from heterozygous salmons with 95% or higher accuracy and can teach others to do as well.

Codominant mutants and incomplete dominant mutants can only be distinguished with data showing whether or not there is a functional gene product. We have no such data for salmon and most other snake mutants; we only have breeding data. Breeding results are exactly the same for incomplete dominants and for codominants, making the terms synonyms at this level. My genetics prof used "codominant" as a catchall for all mutants producing this sort of breeding result because it has fewer characters to type than "incomplete dominant".

If he can't do a better job

Paul Hollander

Disregard the last line in my post just above.

Paul Hollander

I have used dominant for Hypos because you can't distinguish between the heterozygous and homozygous hypos with 100% certainty. So they are not co-dominant. However, by the definition I have of incomplete dominant mutations they are very similar to dominant mutations in the way they work, the variable comes into play with breeding to other mutations. I don't really know if this makes sense. I haven't used the incomplete dominance label before, but in an effort to better explain the characteristics of inheritance for each mutation, I thought this might be a good fit. Perhaps I should revert back. I do not want to misslead anyone, and I feel I have a fairly good handle on this stuff. Based on the phenotypes of boas with Hypo mutant genes, and the variability that does exist, I figured there has to be a reason and the incomplete dominance label may help to signify this. I realize this would be the first use of the term in the boid world.

I think the first step to common ground would be for you to post the definition you have for "incomplete dominant". Then we can see where to go next. Thanks in advance.

Paul Hollander

So from what I've gathered:
Incomplete dominant mutations have similar phenotypes in heterozygous and homozygous forms. When an organism with the mutation is crossed with another unrelated organism the resulting offspring will show similar characteristics of both. Does this make sense, I'm not sure how well I am explaining myself.

I, like Ryan, have been taught by the flower principle. The Red X White = Pink.
Since Hypos have a variety characteristics, and I don't know of any other mutations that could be classified as incomplete dominance (other than wild type) I will use this example. Crossing two hypos with different characteristics will create offspring with components of both. Such has been done by using striped, abberant, high-color, low-speckled, broad saddled, etc.

Now this can also be classified as selective breeding, which it may be better to do so. But so can the flower. By crossing the light color of the white flower and the pigment of the red flower the goal would be a light pigmented flower, pink. So the same can work with Hypo traits. And it has worked. In other mutations with variables everything seems to work at random, but in Hypos breeding certain traits results in certain results. Since these traits are not 100% connected with the Hypo mutation, but are by-products I think of them as the incomplete factors of the mutation.

I mentioned that wild-type boas could be labeled as incomplete dominant as well. We know that wild-type is dominant over recessive mutations, but that wild-type animals with different characteristics can be crossed for new results that are a combination factor.

I realize some of this may sound a little off, I'm not the best at explaining my thoughts. At any rate, what do you think? Right, wrong, good idea, why did I ever come up with it?

>Incomplete dominant mutations have similar phenotypes in heterozygous and homozygous forms. When an organism with the mutation is crossed with another unrelated organism the resulting offspring will show similar characteristics of both.
>
>I, like Ryan, have been taught by the flower principle. The Red X White = Pink.

I was taught by the flower principle, too. When an organism with the mutation (with white flowers, lacking pigment granules) is crossed with another unrelated organism (with red flowers, normal number of red pigment granules), the resulting offspring (the heterozygotes) will show characteristics similar to both (pink flowers, caused by fewer than normal red pigment granules). In other words, the pink flowers show similarities to BOTH homozygous forms rather than just the mutant form. This produces the third, heterozygous (pink flower) phenotype.

>Since Hypos have a variety characteristics, and I don't know of any other mutations that could be classified as incomplete dominance (other than wild type) I will use this example. Crossing two hypos with different characteristics will create offspring with components of both. Such has been done by using striped, abberant, high-color, low-speckled, broad saddled, etc.

Hmm. But aren't there striped, aberrant, etc. boas that are not hypo? That would make striped, aberrant, etc. caused by something other than the hypo mutant gene. I've checked a couple of biological dictionaries, and they said nothing about more than one locus. They were variations on this definition from www.dictionary.com: "A heterozygous condition in which both alleles at A GENE LOCUS are partially expressed, often producing an intermediate phenotype." (Emphasis mine.)

>Now this can also be classified as selective breeding, (snip)

But you can select pink flowers for a hundred years, and they will still keep producing red and white flowers as well as pink flowers. This is not what we normally think of as selective breeding.

I mentioned that wild-type boas could be labeled as incomplete dominant as well. We know that wild-type is dominant over recessive mutations, but that wild-type animals with different characteristics can be crossed for new results that are a combination factor.

It's better to call the wild type gene at each locus the standard against which each mutant is compared to determine whether the mutant is dominant, recessive, or codominant to the wild type allele.

"Wild-type animals with different characteristics" aren't all wild type animals. Many are mutants that happened to be found in the wild. Admitted that boas are variable enough in the wild that it's difficult to make a hard and fast determination of what is and what is not the wild type.

I must logout now and won't be back until tomorrow some time.

Paul Hollander

your input. Good discussion. Thanks!

http://www.salmonboa.com/pdf/JournalHeredity_May00.pdf

If you think he's wrong, you should write a journal article saying why. I think he nailed it.

Caden

There were still several unanswered questions about the trait,and how it performed,we now have the luxury of examining the original data compared to multiple generations of actual breeding results to "fill in the gaps". (The trait has proven itself to be "dominant",not "co-dominant",not "incomplete dominant".) at the time it was written,I believe that the stumbling block that no one could get over was: "if the trait is dominant,why do only half the babies in a given test litter show the trait???"...the answer: "the animals used in the trials were heterozygous examples,not homozygous ( "supers" )at that time the term heterozygous was only used in conjunction with recessive traits,being very new to genetic anomolies,the writer felt that the term "incomplete dominance" best fit the results that had been seen at that point. "Co-dominance" was adopted in an effort to explain why the trait seemed to have a "compoundable" quality when bred to another gene carrier. (the presumption of three distinct,consistant phenotypes.) My input to the thread above would be that, I have actually bred the trait,numerous times...I also have a fairly good "handle" on genetics & its various terminologies. I feel the the trait best classifies itself as "dominant",not because I want it to be,but because this is the classification that most clearly & accurately fits the results that it shows consistantly...let someone write an article proving it "isn't"
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EMAIL quit editing my signature!

And have also talked with Rich about it.