Reptile & Amphibian Forums

Genetics! I have learned much about them but I am still confused about some things. I am under the impression that just because a snake does not show a certain morph it still has the genes.
Here is my question:Is there a small chance that a normal looking Ball Python that has a parent that is pastel (pastel is co-dom gene right?) have offspring from another normal and produce a pastel?
The genetic are there and I am told that pastel is a co-dom so it seems that it could happen even if it is a slim chance.
What do you all think? Or know as a fact?

The pastel gene does not behave as a recessive. Your describing the behavior of a recessive gene. The animal looks like a normal or wild type but carries the gene to produce the visual morph. Better known as a Het. You will not get a pastel by breeding a normal looking ball from a pastel clutch to another normal ball.
Most breeders claim that the normal siblings in a pastel clutch look better than your typical normal. I believe this to be true. So you could breed a real nice looking normal pastel sibling to a high gold and produce some above average balls. They still would not be pastels but they should be nicer than your typical normal.

Hi there,
Genetics are considered theory until proven. The Pastel example you gave is a good place to start. The first Pastel that was found was wild caught. This snake "randomly" appeared, like other wild caught "morphs". Its parents are unknown, so there is no way to find out what they looked like, but we know by looking at the snake it is different. Since the gene was proven to be CO Dom, when bred to a normal, the babies theoretically should be as follows;
1. Half the babies will be Pastel, they will look like and carry the gene
2. The other half will be normal, non gene carrying.
Since genetics are a theory until proven, we can not say that out of 10 eggs, 5 will be Pastel, and 5 will be normal. I have seen this ratio shot to death when out of 8 eggs that hatched only 3 where Pastel and rest where normal. Co Dom traits either have or don't. Recessive genes are the ones that are hidden. Pieds are recessive, and if you bred a Pied to a normal, all your babies would be 100% Hetero for the Pied gene. Non would be hatched as a Pied. You would need a Pied and a Het, 2 Hets, or 2 Pieds to make them.

You are thinking of a phenomenon that the geneticists call incomplete penetrance. In this case, due to other genes and/or environmental factors, an animal looks normal despite having the mutant gene. I understand that this sometimes occurs with at least one of the mutant genes causing extra fingers and toes in humans.

>Is there a small chance that a normal looking Ball Python that has a parent that is pastel (pastel is co-dom gene right?) have offspring from another normal and produce a pastel?

It's not zero, but it is perilously close in this case.

>The genetic are there and I am told that pastel is a co-dom so it seems that it could happen even if it is a slim chance.

First of all, the mutant gene must be there. In my opinion, the mutant gene is not there in 99.9% of the cases.

>What do you all think? Or know as a fact?

If you have a choice between a normal and a normal-looking baby from a pastel x normal, I think the baby from the pastel x normal mating is overpriced if it costs more than five cents (USA) over the price of the normal.

Paul Hollander