Genetics and the "white/albino" inferalanis

[rmelancon]

Question for the genetics gurus out there. Most of us have seen the "white/albino" inferalanis that have been posted here in the past. It has yet to be determined if it is indeed genetic (although most things point to that) and what exactly the mutation should be called, hence the quotes. My question is that if indeed it is genetic would it be possible that one would be able to see characteristics of the trait in the tadpole stage but not in the adult stage of frogs that carry the gene but don't display the trait? The reason that I am asking this is that I have the WC adult pair that has produced the offspring from which the "white" frogs are descended. I have started paying more attention to the f1 tads and notice that every now and again I get a few tads that start out very light in comparison to the the standard solid black tads. I have marked these tads and now that they are about a month old they look pretty much the same as the others, solid black. I'm wondering if that could be any indication that they carry the gene?

Thanks,
Robb

[mydumname]

I am guessing you are going to hold some of these "carriers" back to breed them and see what happens. Seems like that could be a self taught lesson, down the road though. I don't know if recessive traits can seen. I would think it is all in the DNA makeup. Someone else will hopefully share more on this.

[Ben_C]

Robb,
I have also produced amelanistic tincs (patricia's though) and am fairly certain that it is a genetic mutation. It actually, from the clutches i've produced, been a very simple recessive mutation (25% of my offspring have the double recessive and are amelanistic).
As for your question:
"...would it be possible that one would be able to see characteristics of the trait in the tadpole stage but not in the adult stage of frogs that carry the gene but don't display the trait? "

I would say that in this case *probably* not. If all tadpoles hatched out white and then expressed melanin later in life it could be possible in that the mutation just delays expression of pigment. HOwever, since my tadpoles (75% Of them anyway) hatch out pigmented, then develop normally, I would say that the chances are that you would not see the amelanistic trait in tadpoles but not the adult stage. HOwever, my mutation may be COMPLETELY different than the inferalanis one that you are referring to. Without decent analysis of these mutations we're just speculating...
hope this helps,
Ben

[mydumname]

I am surprised this post ended without much participation.

Many gene variants are not clearly/cleanly dominant or recessive. Sometimes, with only one copy of the "good" gene, only half the normal gene product is made and you will see an appearance somewhere between fully abnormal and normal. I don't doubt that at certain stages of development the abnormality appears more pronounced in many genes and their variants. But I have no specific knowledge about such color-related genes. [genetic jargon reduced for public consumption ]

Steve

[steelcube]

Just want to point out something that might have been overlooked:

If it follows Mendelian's, you have one carrier parent...

The albinos will show up in F2, but not F1.

...

[rmelancon]

In this case that is true, all the "white" frogs are f2 from f1 siblings.

What is Mendelians?

[steelcube]

Here's a link that explain what Mendelian is:

http://web.mit.edu/esgbio/www/mg/crosses.html

I'll post what I meant by one carrier parent later (or if others would)

SB

[Michael Shrom]

I think it is a simple recessive trait. Only one of Robbs' frogs is carrying it. That would mean about 25% of the offspring from that pair are carrying it. When two heterozygous carriers of the simple recessive gene mate about 25% should be albino. 25% should be normal genotype and 50% should be normal phenotype but have a genotype where the recessive gene is present. Time will tell. As far as I know none of the "albinos" have reached maturity yet. If or when the "albinos" reach maturity it should be easy to do some back crosses to figure out what is going on. Of course their is a possible it will be a weak trait and they will all fail to thrive. From early reports it doesn't seem that this is the case.

[KeroKero]

I highly doubt the "lighter" tads are showing the trait that in F2s produce albinos (I prefer the laymen's term to anything scientific, as it encompasses more, and is more general). Simple genetic traits (such as the implied recessive here) are much like an on/off switch, in this case they either have melanin or they don't. This is not a co-dominant trait, so you don't have an animal thats only carrying "half" outwardly showing signs of the gene (this is the only case off the top of my head where a carrier would outwardly show signs of a genetic trait like Robb implied).

In the albinos, the tad showed an interesting color change as it grew... basically whatever new cells the tad developed lacked melanin (which would imply the melanin containing cells are left over from the cells mommy had in the egg) creating an interesting patchwork of colored/noncolored cells. I would take a wild guess and say an albino female would lay melanin-lacking eggs (white), and the tadpole would start out white and either continue to stay that way (albino) or if the male sperm donor didn't transmit an albino gene, the tadpole would show melanin in the new cells as it grows (opposite of what we see in the albino tads). Simple on/off.

As far as I understand... the same system and genetics controls if melanism is expressed in the tadpoles and adults (the cells don't switch from albino to non-albino or the other way around just because of metamorphosis), while the cells do get swapped around a bit during metamorphosis, the colors themselves are produced (or not produced) the same in both stages. The only thing I can think of where a lack of a color in one stage is not noticable in the other, would be with colors only present in one stage.