Genetics...

[Pythagoras]

Ok, here goes. A "het" is short for heterozygous, meaning it carries the gene to produce the "morph" (like an axanthic, for example), but it looks like a normal. If it is homozygous, it is the visual morph. Like the snake pictured above is a homozygous, because you can SEE that it is an axanthic. If it is 100% het for axanthic, that means it came from breeding an axanthic with a normal.
Jennifer

Not to make things more confusing, but I believe the actual definition of heterozygous is offspring that only carries one gene of a certain characteristic. This includes co-dom morphs like the Pastel. Offspring that carries a pair of genes (one from each parent) is call homozygous. So, just as it takes two het. Albinos to produce a homozygous albino, it takes two Pastels to produce a homozygous Pastel. We call the homozygous mutation "Super-Pastel", and we call the heterozygous mutation "Pastel." Het, Homo, and Double-Het have nothing to do with anything you can SEE in your animal.

We describe the way you can SEE traits being carried through generations with words such as Simple Recessive, Double Recessive, Dominant, and Co-Dominant. Simple Recessive means that the offspring require the gene for a certain trait to be inherited from both parents in order for the trait to be visible. Double Recessive means that the offspring require the genes for 2 different traits to be inherited from each of the two parents in order for the trait to be visible. Dominant means that the offspring only require the gene for a certain trait to be inherited from one of the parents in order to be visible. In a Co-Dominant mutation, the offspring will appear different than a "normal" if the trait is inhereted from only one parent (heterozygous), just as a Dominant. However if the trait is still inhereted from both parents, then the visible mutation appears both different from a "normal" and different from the "het" form of the mutation.

Sorry about the play on words....

[Pythagoras]

I think the "het" form of a codom is called and "incomplete codominate"??? Not sure though....little help here?

[Marla]

There's 4 types of dominance related to ball morphs:
dominant, which is when it masks the effects of recessive genes and only requires one gene to determine phenotype
recessive, which requires 2 genes to determine phenotype
co-dominant, which has a different phenotype for each gene count (0, 1, or 2)
incompletely dominant, which also has a different phenotype for each gene count (0, 1, or 2)

The difference between incomplete dominance and codominance is that with incomplete dominance, the two genes blend into a middle ground and in codominance both are expressed. For example, with a flower that comes from a parent flower with two white genes and a parent flower with two red genes, incomplete dominance results in pink, while codominance results in a red and white flower. Regardless of which type of dominance it is, if the flower got 0 red genes, it would be white, and if it got 2 red genes, it would be red, so the ones with one red gene are visibly different from the ones with one or two.

[snakeys1996]

i understand how the genetics work, but i DEFINANTLY dont have the time, money, or a mom who would approve of me snake breeding. it must be very rewarding watching a morphed snake hatch though

[Pythagoras]

Ok....thanks! So relating to ball pythons...Pastel and SuperPastel are co-dominate. What are spiders? I think there is a "super" form, but it's not visible....but 100% of a "supers" offspring are spider. Does that make spiders incomplete dominate?

Thanks!

[Marla]

From what I have gathered, spiders were suspected to be either incompletely dominant or co-dominant, but have recently been described as actually being dominant, meaning there are no super spiders. If it's simple dominant, then yes, 100% of the offspring of one with both genes for spider would be spiders. As far as pastel goes, I don't think it's been determined whether it's actually co-dominant or incompletely dominant yet. Randy will probably jump in and correct me if I'm wrong.

Mojave and woma morphs are also believed to be one of the lesser forms of dominance. Cinnamon pastel is supposed to be either dominant or one of the lesser forms of dominance.

[JLC]

i understand how the genetics work, but i DEFINANTLY dont have the time, money, or a mom who would approve of me snake breeding. it must be very rewarding watching a morphed snake hatch though

Someday, though...if you really want it. I know my breeding projects are years down the road...but they're definitely there! It's good to have exciting goals!