Reptile & Amphibian Forums

General Question.

What are the possiblities if two pattern morphs cross? What I mean is, lets take two made up Dominant morphs...The Checkerboard and The Crooked stripe. Notice both are patterns, not color morphs. A certain percantage of the young would be CheckerboardXCrooked. When you cross the two patterns, would they tend to blend, or is it possible for one "overwrite" the other? Are both possible? I guess, if there are any examples, they would be most common with ball morphs, but they are not my specialty, so I just don't know. Any ideas anyone?

Shawn

>What are the possiblities if two pattern morphs cross? What I mean is, lets take two made up Dominant morphs...The Checkerboard and The Crooked stripe. Notice both are patterns, not color morphs.

Two pattern morphs, and both are produced by mutant genes that are dominant to normal.

The result would probably look like one, like the other, like a combination of both, or more or less intermediate between the two.

IOW, combining checkerboard with crooked stripe could produce checkerboard, crooked stripe, or crooked checkerboard. From the names, I would not expect a crooked stripe through the middle of the checkerboard.

That's the best prediction I can make. A reliable psychic could do better, if you can find a reliable psychic.

Paul Hollander

Yes, I came to those same conclusions myself. I guess what I mean to ask is, has anyone ever seen one pattern morph override another? In this case, what if you didn't produce all three, but only a clutch of crooked stipes, normals, and checkboards. Has this been the case with any crossed patterns that anyone knows of? As far as I know, noone have proven it.

My logic here, is that like a spider ball cross normal, half become spiders, half are normal. In my sample case, both are a "morph", but can one override the other (sort of like how the spider pattern overrides the normal)? Are there different levels of dominance? Has this been proven with any other organisms?

Tough question I know, and ligically kind of difficult ot follow. I hope I am communicating it well enough?

S~

>I guess what I mean to ask is, has anyone ever seen one pattern morph override another?

Yes, I have seen it in pigeons.

The normal pattern on the wings is a slate gray ground color with two parallel black bars. Checker produces a black and gray checker pattern on the wings and is caused by a mutant that is dominant to the normal allele. T-pattern produces wings that are mostly black and is also produced by a mutant gene that is dominant to the normal allele. The T-pattern mutant gene and the checker mutant gene are also alleles. The T-pattern allele is also dominant to the checker allele, so if you have a bird with a T-pattern mutant gene paired with a checker mutant, the bird looks like a bird with two T-pattern mutant genes. As far as I know, no one has found multiple alleles at one locus in the ball python. Yet. A case of multiple alleles has turned up in the corn snake, and another is in the black rat snake.

If you want two dominant mutants that are not alleles, in the pigeon a dominant mutant named spread produces a solid black coloration all over the body. A bird with both spread and checker mutant genes is solid black, like a bird that has the spread mutant gene and lacks the checker mutant gene.

"Epistasis" is the standard genetics noun for a mutant gene that maskes the effects of an independent mutant gene. The verb form is "epistatic", as in "the spread mutant gene is epistatic to checker." The T-pattern mutant is dominant to the checker mutant and not epistatic to the checker mutant because the two mutants are alleles.

Paul Hollander