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What would the result be of breeding a striped corn to a snow corn? I was under the impression that each trait was a simple double recessive. When I plug those factors into my genetics program, the results I get say 100% will be normals, which will be het for stripe and snow. Is this the case? If so, where is the dominant normal gene residing? I'm also curious about zig-zag corns bred to snow corns also. Any light that anyone can shed on this is appreciated. Thanks!

A stripe X snow would produce all normal looking snakes that are het for strip, amel, and anery. The dominate gene for the stripe is the normal pattern of the snow and the dominate gene for color would be the normal color in the stripe. As far as aztec some people say it's due to stress during incubation, but it has been proven genetic as a simple recessive gene.

tom

xtremeherps@yahoo.com

Here's my answer to where the normal genes come from.

Corn snakes have 18 pairs of chromosomes. Let's assume that the amelanistic mutant gene has its residence (locus) on one pair, the anerythristic mutant gene's locus is on a second pair of chromosomes, and the striped mutant gene's locus is on a third pair of chromosomes.

I'm going to try some very simple ASCII art, which requires symbolizing the genes. So here is the list of symbols:

a = amelanistic
A = normal version of the amelanistic gene

ax = anerythristic
Ax = normal version of the anerythristic gene

s = striped
S = normal version of the striped gene

Snow is a combination of amelanistic and anerythristic. This snake also has normal genes at the striped locus. Here are the three pairs of chromosomes:

---a-------
---a-------

-----ax-------
-----ax-------

--S----
--S----

The striped corn has a pair of striped mutant genes symbolized by "s". It also has normal genes at the amelanistic locus and the anerythristic locus:

---A-------
---A-------

-----Ax-------
-----Ax-------

--s----
--s----

Take one of each pair of chromosomes from each parent. It actually does not matter which because for our purposes, one member of each pair is identical to the other member of each pair. Each baby gets these chromosomes:

---A-------
---a-------

-----Ax-------
-----ax-------

--S----
--s----

And that is how all the babies from a snow x striped mating come to look normal and are heterozygous for amelanistic, anerythristic, and striped. The snow corn provides the normal gene at the striped locus, and the striped corn provides the normal gene at the amelanistic locus and the normal gene at the anerythristic locus.

Paul Hollander