Reptile & Amphibian Forums

I have produced the Peanut Butter brooksi for the last three seasons and I have never produced a female Peanut Butter.
The Peanut Butter recessive trait starts out amelanistic but then gets more pigment and turns into a type of hypomelanism as it matures.
The pic on the bottom shows a PB male on the left. A female het PB in the middle and a male het PB on the far right. Note that the het female (middle) is lighter than the het male PB (right):

To date ('99 when the first male Peanut Butter was produced) there has never been a FEMALE PEANUT BUTTER PRODUCED. I have been the only person to produce the PB morph in the last three years and I have also never produced a female PB.

On a side note there is an unusual color difference in the het males and het females of this morph. Here is a pic which is shows a typical female het Peanut Butter and a typical het male Peanut Butter taken this year. They are both clutch mates from '03 and yet both are distinctively different in color.
MALE HET PB:

FEMALE HET PB:

1)So, whats going on with this reccesive gene? How does the Peanut Butter morph start out amelanistic lavender and then turn hypomelanistc?

2)Is it possible that recessive traits can be also sex linked?

>1)So, whats going on with this reccesive gene? How does the
>Peanut Butter morph start out amelanistic lavender and then
>turn hypomelanistc?

How is this different from the normal color changes many snakes undergo in the first few years of their lives? Some pigments are lacking or minimal in the new-hatched snake and increase as the animal matures.

>2)Is it possible that recessive traits can be also sex linked?

Sure. Dominant ones too. But you'd expect sex-linked recessives to come to expression more frequently in females than in males. That's because snakes have ZZ male/ZW female sex determination. One would expect any gene on the Z chromosome in the female to be expressed (i.e. hemizygous) but a recessive sex-linked gene would have to be on both Z chromosomes in the male to be expressed (homozygous). You don't say what matings you've made and how many progeny of each sex you've produced. If the gene is not sex linked and you have been mating heterozygotes, you can expect only one baby out of 8 to be a homozygous Peanut Butter female. You would have to produce a lot of progeny just to be sure the lack of such females is not just happenstance.

If you want to find out mode of inheritance, mate that female you're calling a "het" to a Peanut Butter male. If the Peanut Butter phenotype is due to a single gene mutation, that cross should tell you how it is being inherited.

Bigfoot