Super forms

[Lesserlove]

How does the super form occur? Is it the recessive traits from a co dominant morph? What about the dominant traits from a co dominant morph? RR?

[Ryan Chin]

I got half way through typing an explanation...then decided to post this.

http://www.newenglandreptile.com/new...enetics-supers

[Lesserlove]

So an rr from Rr x Rr would be the normal and the RR would be the super and that how it's guaranteed the base morph?

[satomi325]

A 'super' is the homozygous form. It has two of the same or similar alleles that lie on the same loci.
Take pastel for example. A Super Pastel is the homozygous form of a pastel. In this case, a pastel can be seen as a het. Super Pastel. Or the heterozygous form.

The Super Pastel carries 2 pastel genes. (PP)
A Pastel carries 1 pastel gene and 1 normal gene. (PN)
A Normal is just (NN)

When a Super Pastel breeds to a Normal, it can only pass a P gene to it's offspring. So the offspring gets one P gene (from the Super Pastel parent) and one N gene (from the normal parent). Since the offspring now carries a P and N gene, it is a pastel.

PP x NN = PN
PP x PN = PP, PN
PN x NN = PN, NN

[Lesserlove]

Is that how it is with all co dominant morphs? XN? So in the super form, why does the phenotype change? Is it that it magnifies the morphs original characteristics?

[paulh]

Is that how it is with all co dominant morphs? XN? So in the super form, why does the phenotype change? Is it that it magnifies the morphs original characteristics?

Not all codominant morphs are caused by a mutant gene paired with a normal gene. It could be caused by a mutant gene paired with a different mutant gene (XY). But the most common type is a mutant gene paired with a normal gene(XN).

A normal gene is the most common gene at a given location in the chromosomes. A mutant gene is NOT the most common gene at a given location in the chromosomes. A snake looks normal if it looks like most of the same species of snake crawling around in the wild.

A mutant gene and its corresponding normal gene can make three gene pairs:
1. 2 copies of the normal gene
2. 1 normal gene and 1 mutant gene.
3. 2 copies of the mutant gene

Each mutant gene is recessive, dominant, or codominant to the corresponding mutant gene. When a normal and two (or more) mutant genes have the same location in the chromosomes, a mutant gene is always recessive, dominant, or codominant to another mutant gene.

The mutant gene is recessive to the normal gene if
1. 2 copies of the normal gene make the snake look normal. (Appearance is normal.)
2. 1 normal gene and 1 mutant gene makes the snake look normal. The effect of the normal gene prevents the effect of the mutant gene from being detectable. (Appearance is normal.)
3. 2 copies of the mutant gene produces the full effect of the mutant gene. (Appearance is albino.)
Example: Albino mutant gene and corresponding normal gene in ball pythons in the above.

The mutant gene is dominant to the normal gene if
1. 2 copies of the normal gene make the snake look normal. (Appearance is normal.)
2. 1 normal gene and 1 mutant gene makes the snake look like a snake with two copies of the mutant gene. The effect of the mutant gene prevents the effect of the normal gene from being detectable. (Appearance is pinstripe.)
3. 2 copies of the mutant gene produces the full effect of the mutant gene. (Appearance is pinstripe.)
Example: Pinstripe mutant gene and corresponding normal gene in ball pythons.

The mutant gene is codominant to the normal gene if
1. 2 copies of the normal gene make the snake look normal. (Appearance is normal.)
2. 1 normal gene and 1 mutant gene makes the snake look neither normal nor like a snake with 2 copies of the mutant gene. Both the normal gene and the mutant gene have an effect on the snake's appearance. (Appearance is lesser platinum.)
3. 2 copies of the mutant gene produces the full effect of the mutant gene. (Appearance is blue-eyed white.)
Example: Lesser platinum mutant gene and corresponding normal gene in ball pythons.

Platinum in the ball python is a example of a mutant gene that is codominant to another mutant gene. Both mutant genes must have the same location in the chromosomes. The lesser platinum mutant gene is codominant to the Daddy gene
1. 2 copies of the lesser platinum mutant gene produces the full effect of the lesser platinum mutant gene. The snake is blue-eyed white
2. 1 lesser platinum mutant gene and 1 Daddy mutant gene makes the snake look neither blue-eyed white nor like a snake with 2 copies of the Daddy mutant gene. Both mutant genes have an effect on the snake's appearance. The snake is platinum, which is lighter than a snake with a lesser platinum gene paired with a normal gene.
3. 2 copies of the Daddy mutant gene produces the full effect of the Daddy mutant gene.

Clear as mud?

[Lesserlove]

.... You lost me a bit there lol okay so you may have answered this and I just didn't get it, so do single gene animals carry the normal gene? Like spiders pastels, things like that?

And I still don't quite understand how the supers have a different phenotype... Good info I'm just slow on the uptake here lol. Ill read it a few more times.

[Pythonfriend]

snakes have two sets of chromosomes, one from mom and one from dad.

that makes the whole genome somewhat fail-safe and redundant. If one gene is broken, the other copy just takes over.


so in a codominant morph, the snake has one chromosome that carries the morph and also a normal chromosome, and the two interact. So you have two influences, the morph is somewhat expressed but also somewhat overshadowed by the influence of the normal chromosome.

in the super form, the whole chromosome pair is affected. The snake got the morph from both mom and dad, and at this place there is no normal chromosome for the snake to fall back on. That is why super-forms often look so dramatically different.

its easier to understand with recessives, like albino. In albino, the gene responsible for producing the black pigment is broken, so you get a white and yellow snake. But if the snake only has one copy of it, it looks completely normal, its just "het for albino". if in one chromosome the gene to produce black pigment is broken but the other chromosome is normal, the snake just uses the normal copy to make the black pigment. And you see nothing, it looks normal. But if you get two copies of it, then the snake really completely loses the ability to make black pigment and you get a visible albino.


Maybe your mistake is that you think the normal chromosome just does nothing, but thats not true, if a normal copy is present then this normal copy does a lot. and when both chromosomes carry the morph and there is no normal chromosome for the snake to rely on, it makes a big difference.

[Lesserlove]

Ahhh okay I think I get it now, thanks guys (:

[paulh]

.... You lost me a bit there lol okay so you may have answered this and I just didn't get it, so do single gene animals carry the normal gene? Like spiders pastels, things like that?

And I still don't quite understand how the supers have a different phenotype... Good info I'm just slow on the uptake here lol. Ill read it a few more times.

I have not been on the web for a while.

When we say a single gene animal, we mean an animal with a single mutant gene in the gene pair. A single gene spider ball python has one spider mutant gene and one normal gene in the gene pair. A single gene pastel ball python has one pastel mutant gene and one normal gene in the gene pair.

As Kutilein wrote, a normal gene does something rather than nothing. A mutant gene either does nothing or does something different from what the normal gene does.

Here is a way to think of it. Norman (normal gene) and Mary (mutant gene) are in a car approaching an intersection. Here are the possibilities.
1. Norman has two hands on the steering wheel. Mary is not in the car. Car always turns left at the crossroads.
2. Norman is not in the car. Mary has two hands on the wheel. Car always turns right at the crossroads.
3. Both Norman and Mary are in the car. Norman has one hand on the steering wheel, and Mary has one hand on the wheel. Which way does the car turn?

3a. Norman has one hand on the steering wheel and Mary has one hand on the wheel. Mary is recessive to Norman. Norman tries to turn left, and Mary tries to turn right. Mary applies much less force to the wheel than Norman does. Car turns left.
3b. Norman has one hand on the steering wheel and Mary has one hand on the wheel. Mary is dominant to Norman. Norman tries to turn left, and Mary tries to turn right. Mary applies much more force to the wheel than Norman does. Car turns right.
3c. Norman has one hand on the steering wheel and Mary has one hand on the wheel. Mary is codominant to Norman. Norman tries to turn left, and Mary tries to turn right. Norman and Mary apply equal force to the wheel. Car goes straight instead of turning.