> From: [EMAIL PROTECTED]
> Date: Sun, 29 Jul 2001 06:52:56 -0400
>
> In a message dated 7/27/01 6:48:29 PM Eastern Daylight Time,
> [EMAIL PROTECTED] writes:
>
> << Hello Jason,
> It's possible that he had two different "types" of albino adults.
> Breeding a Rainwater gecko to a Tremper animal will produce
> normal-looking babies.
> >>
> I'm no expert, but if they look normal, than they are not albino - correct?
> And then this would mean that one of the adults was het not albino.
Animals are albino if one of the enzymes involved in the production of
melanin pigment is defective. There are several steps involved in this
synthesis, catalysed by several different enzymes. Each enzyme is coded
for by a different gene, so a mutation in any of these genes can cause
albinism.
In leopard geckos, there are at least two separate genes that have had
mutations for albinism. One is the gene for tyrosinase, and one is the
gene for another enzyme in the series. Which one hasn't been determined
yet, AFAIK.
If you want a silly analogy, imagine baking a cake. One step is 'pour
batter into pan' and another is 'bake in the oven'. If you can't put
the batter into the pan, you won't get a cake, even if the oven is ok.
If the oven doesn't work, it doesn't matter that you can pour the batter
into the pan. You won't get a cake!
> However, if we consider only the one question- What is an albino leopard
> gecko- we can create a definition acceptable to us as a group. We owe it to
> our novice members who may not know what they are paying top dollar for, or
> who breed two "albinos" together and get normal offspring.
Tremper albinos have a different gene mutated than do the Rainwater albinos.
One is a mutation that produces a defective tyrosinase enzyme, and the other
affects some other enzyme involved in melanin synthesis.
These are separate traits, just as patternless and blizzard are. It's
remarkable that both albino mutations showed up about the same time, allegedly
in offspring of animals from the same importation.
> How bout this for starters- How can an "albino" look normal?
It can't.
> And How can two albinos breed normal offspring?
Let's call the defective gene in tyrosinase positive leos Gene X. If you
have one animal homozygous for tyrosinase negative albinism, it is unable
to produce good tyrosinase, so it will be an albino, even though its Gene X
is perfectly ok. Another animal with perfectly good tyrosinase genes may
be homozygous for defective Gene X, and also appear as an albino. If you
cross these animals, each offspring will get a good copy of each gene from
one parent, so they will appear normal, although they are heterozygous for
both defective genes. If you cross these offspring among themselves, you
will get some of each form of albinism back, as well as normal appearing
animals.
> Anybody?
I hope this helps!
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