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I'm relatively new to boas, so can someone explain to me why Hypo X Hypo = "Possible" Super? Is Super a dominant trait? I don't know the difference between codom and dom, I guess. I am guessing that a dominant trait is only proven by breeding? and all the babies of a dominant trait show that trait. Is this correct? Thus, Super X Normal = Hypos, yes??? I understand codom, because of Pastel B/P's, but as far as I know, there are no dom B/P traits. Sorry to ramble, and thanks to anyone who can clarify this for me!
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"I am a cop, and you will respect my authoritae!"-Cartman

Well, from what I understand there are a few different lines of hypos in the boa world. Whether they are affected by different genes or not remains to be seen. Salmon is the most common of the hypo traits and I honestly don't know if it is a codominant or dominant trait. It seems sometimes the homozygous is different from the heterozygous and sometimes it has to be proven. Perhaps it is dominant and the better looking F2 offspring are a result of line breeding rather than the trait being codominant. Have I lost you? I'll try and address your questions.

>>I'm relatively new to boas, so can someone explain to me why Hypo X Hypo = "Possible" Super?

This is because in the case that the hypo gene is dominant, a hypo X hypo will produce a pile of hypos some of which will be heterozygous and some of which will be homozygous (supers). The problem is...If this is a dominant trait there will be know way to distinguish the heterozygous hypos from the homozygous hypos (supers)....Therefore they would be referred to as "possible supers"

Is Super a dominant trait?

No, super refers to an animal that is homozygous as aposed to heterozygous. Any homozygous animal that is codominant will have a Super form (ie. super tiger retics & super pastel BPs). I don't think that the term Super should be used with dominant traits since they do not have any characteristics that are different from the heterozygous form of the trait.

I don't know the difference between codom and dom, I guess.

dominant is the same as codominant except for the fact that in codominant traits the heterozygous and homozygous traits are distinguishable where as they aren't in dominant traits.
Another way to look at it would be that with dominant traits, the normal (wild type) gene is simple recessive. In other words, the heterozygous dominant trait is het for normal and the homzygous is not. If you wanted to prove a het albino (can't distinguish from normal), you would breed it to an albino to see if there were any albinos. Similarily, if you want to know if you have an animal with the heterozygous or homozygous form of a dominant trait (effectively is it het for normal), you would breed it to a normal. If you get normals it is het for normal (ie heterozygous for the dominant trait), otherwise it is not het for normal (ie homozygous for the dominant trait).

I am guessing that a dominant trait is only proven by breeding?

correct

and all the babies of a dominant trait show that trait. Is this correct?

Yepper!

Thus, Super X Normal = Hypos, yes???

You got it!!

I understand codom, because of Pastel B/P's, but as far as I know, there are no dom B/P traits. Sorry to ramble, and thanks to anyone who can clarify this for me!

Then you know that Pastel BPs also come in the homozygous form (Super Pastels) right? I don't know of any dominant traits in BPs either but there are a number of unproven codominant traits (mojave, spider etc) that may not prove out to be codominant which would make them dominant by default

Having fun yet ??
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mark

: I'm relatively new to boas, so can someone explain to me why Hypo X Hypo = "Possible" Super? Is Super a dominant trait? I don't know the difference between codom and dom, I guess.

First, Rich Ihle named the gene causing his hypos "salmon". It's the most common hypo, but not the only one. So this post is for salmons, and not the other hypos.

"Super" is herper slang for "homozygous for a dominant/codominant mutant gene". IOW, chromosomes come in pairs, and as genes are pieces of chromosomes, genes come in pairs, too. A salmon has a salmon mutant gene in one chromosome, and a normal gene in the corresponding spot in the other chromosome. In standard genetics terminology, this snake is heterozygous for salmon. A "super salmon" is homozygous for salmon as it has a salmon mutant gene in both chromosomes.

A dominant mutant is one where the heterozygote (one salmon and one normal gene) cannot be reliably distinguished from the homozygote (two salmon genes). A codominant mutant is one where the heterozygote (example: pastel in the ball python, produced by one pastel and one normal gene) CAN be reliably distinguished from the homozygote (example: super pastel or opal in the ball python, produced by two pastel genes). Nature is sloppy; some dominant mutants have heterozygotes that can SOMETIMES be distinguished from the homozygotes. Salmon seems to fall into this category. But as the heterozygote can't be RELIABLY distinguished, it's better to call salmon a dominant than a codominant mutant.

BTW, some herpers use "dominant" when they mean "homozygous codominant". This is not standard genetics terminology and should be gently discouraged.

: I am guessing that a dominant trait is only proven by breeding? and all the babies of a dominant trait show that trait. Is this correct? Thus, Super X Normal = Hypos, yes??? I understand codom, because of Pastel B/P's, but as far as I know, there are no dom B/P traits.

Dominant, codominant, and recessive genes must ALL be proven by breeding. If a snake has either one or two copies of a dominant mutant gene, then the snake shows the mutant's effect. But some babies of parents with the dominant mutant do not receive the mutant gene and therefore do not show the effect. This is why two (heterozygous) salmons can produce some normals.

Salmon (heterozygous) x salmon (heterozygous) produces 1/4 salmon (homozygous or "super salmon" ), 2/4 salmon (heterozygous), 1/4 normal. Here's the Punnett square, with Sa meaning the salmon mutant gene and either no symbol or a symbol (depending on whether the HTML will let the plus symbol go through) meaning the normal gene:

| Sa | |
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Sa | Sa//Sa | Sa// |
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| Sa// | // |
---------------------

// = a pair of chromosomes.
Sa//Sa = 1/4 homozygous salmon
Sa// = 2/4 heterozygous salmon
// = 1/4 normal

When you can't tell the difference between the heterozygous and homozygous salmons, then you can call all of them possible homozygotes (possible supers).

Clear as mud? 8-)

Paul Hollander

I've been wondering for a long time whether the Salmon gene was dominant or codominant. I've seen spectacular looking "Supers" and some mundane "Possible Supers" which has always confused me.

So the Salmon trait in boas is a dominant trait that sometimes appears different in the homozygous form than it does in the heterozygous form OR a codominant trait that sometimes appears the same in the homozygous form as it does in the heterozygous form, depending on how you look at it? I guess that makes sense. Everything doesn't always fit in a neat package the way we might like it to.

Thanks for clarifying this at long last Paul!
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mark

Nature doesn't have to fit into the black and white categories that humans set up. A similar deal is striped in the California king snake. Blasphemy though it might be to mention a colubrid on the boa forum. 8-)

Unfortunately, I've only seen pictures of salmons, read Rich Ihle's paper in the Journal of Heredity, and read the various salmon threads in this forum. Without a good bit of experience with the live snakes, I couldn't really say how easy it is to correctly separate the heterozygotes from the homozygotes. Though I do like to look at the posted pictures and make a guess. For example, Boa Afficionado's snake in the "Quick Salmon Hypo Picture" thread (a bit down from this one) looks like a homozygous salmon to me. This is based on the very narrow, bar-like saddles on the forward half of the body. What do you think?

Paul Hollander

I appreciate the clarification on dom/codom. I think I am clear as can be on the hypo issue...Thanks again!
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"I am a cop, and you will respect my authoritae!"-Cartman

First off, thanks you guys for posting this... I always
like a re-fresher when it comes to the salmon genetics,
one of the more confusing morphs. lol

Above is my F1 salmon (salmon male bred to normal female)
I believe the boa afficianado's hypo is expressing the homo-
state of the trait. You can see the difference in the size,
shape and deffinition of the saddles as compared to F1s...
I like to guess at what they are as well, but I have seen
some that were het and some that were homo that appeared to
be the opposite. (I belive it was Rich himself who posted
a thread a bit back about how he bred two females poss supers
and the one he thought was a super ened up being het and
the other he didn't think was the homo turned out to be.)
Ahhhhh boas... fun fun!