White tadpoles?

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They're probably not albino :( but i did feed them the blood worms and they didn't take too them as well as i thought they would, being gutses and all.
 
Ok gang, these guys just aren't ment to survive. Evertime they get to the stage where the front legs come out they die. Only 2 left now,don't have much hope for them though. They still eat like crazy and are a good size but they just wont morph past that point. Sad i know but i thought i should report for those who are interested ( thanks for reminding me Bretsta ).
 
Ok gang, these guys just aren't ment to survive. Evertime they get to the stage where the front legs come out they die. Only 2 left now,don't have much hope for them though. They still eat like crazy and are a good size but they just wont morph past that point. Sad i know but i thought i should report for those who are interested ( thanks for reminding me Bretsta ).

Very interesting, thanks for sharing.

I believe that most likely, what is going on here is albinism caused by a large DNA deletion. As we all know, albinism is caused by a genetic defect which stops some part of the genetic program which produces melanin. If the mutation is small and only affects one on the critical genes involved with melanin production (and that gene doesn't do anything else of importance), you'll get a healthy animal which is normal other than not having melanin.

Some mutations are far larger though. Some mutations involve large sections of DNA being deleted or disabled. In these animals where a considerable amount of DNA is lost, several biological functions can not proceed, which can result in animals which are unhealthy or animals which die.

Interestingly, new genes get switched on as animals age and develop, and there are critical times when lots of new genes are switched on. In early development after conception, lots of new genes are being used for the first time (this is pretty obvious, because genes are needed for anything to happen, and you can't use genes before you exist). Towards the later stages of gestation (or incubation) fewer and fewer new genes are being switched on because fewer and fewer new things are happening. Then suddenly, bang, the animal is either born or hatches, an immediately a lot of new biological functions are required, and tested, and lots of new genes are suddenly required; this is the second critical time for gene testing, and it is this reason that lots of animals develop well then suddenly die around birth or hatching.

After birth/hatching, things settle down again and there isn't another massive spike in new genes being switched on for the first time until puberty, and then (in females) reproduction.

Frogs are interesting in that they go through metamorphosis, and at critical stages during metamorphosis new genes are switched on as they are required for the first time. It looks to me like your albinism is caused by a genetic deletion or disabling of multiple genes rather than just one gene, and unfortunately, one of these is critically important and is required/switched on at the stage where the front legs comes through. Cases like this (where albinos or other mutants are sick or can't live but their siblings are perfectly fine) are very different from cases where the mutants are sickly or die, but the hets and normal siblings are also sickly. If the normal siblings are also unhealthy it usually indicates that you're simply working with a genetically poor line, and outcrossing will probably eventually fix things up quite nicely.

Unfortunately, this type of deletion involving multiple genes is practically impossible to fix (the easiest and possibly cheapest way might be to spent a few million dollars getting geneticists to tamper with the DNA in a lab - clearly not a realistic option, or even a legal one in Australia, and it would be easier to recreate the condition in the lab starting with a normal animal - still very difficult and expensive).

Different again are things like the albino Bearded Dragons, which have problems most likely associated with pleiotropy (similarly impossible to breed out, but for different reasons).

Your tadpoles are very interesting, thanks for keeping us updated. It will be interesting to see if some people are interested in obtaining hets/possible hets for the purpose of creating more albinos to observe until death in metamorphosis, even if they will never be viable. I can think of a few other reptile cases where hets for non-viable morphs which either die at hatching or don't live long at all are more popular than normal conspecifics. If someone comes up with a line of healthy albino Green Treefrogs it would be interesting to cross your hets with their albinos. If the deleted genes of yours include the deleted/disabled gene in the healthy ones, the result would be healthy albinos which are het for death, and if you crossed them you wouldn't be able to tell the healthy albinos from the albinos het for death or the albinos homozygous for death at metamorphosis (although the homozygotes would reveal themselves at metamophosis, and the surviving metamorphs would be 67% hets for death).

If anyone is wondering, yes I've summarised and simplified to avoid the post being impossible to understand and to keep it under several pages. If you want me to expand or explain something, I'd be glad to.
 
At least one person did! :lol:

Probably a greater challenge than understanding it is simply bothering to read the whole thing ;) Well done!
 
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