# albino genetics



## josh raysin (Nov 28, 2005)

ok im no genetics expert, but in my first day of genetics class we looked at crosses like albinism. now not to pick on any 1 person but ive seen several post about het for albino offspring. for those of you claiming to have them, in a cross of parents het for albino ("Aa x Aa"), 25% will NOT be het for albino("AA"), 50% will ("Aa")and 25% will be albino ("aa")(assuming they live) so therefor you only have a 66% chance of having a het for albino (albinos dont count here since you know they are "aa")frog without having bred it to find out for sure. please correct me if im wrong.
later josh


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## Catfur (Oct 5, 2004)

But if you breed an actual albino to a regular frog, than all of the offspring will be 'het' for albino, if you breed a known het to a normal, than that is 50%, and you can get just about every other percentage one way or another.


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## xfrogx (Jul 5, 2006)

The frogs can carry the trait for many generations, thats why people need to keep track of where there frogs come from. By the way im selling an alanis thats het for albino its grandfather was albino. And only one of this alanis's siblings came out albino. ( sorry for hijacking I kinda did  )


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## Ben_C (Jun 25, 2004)

This also assumes that the trait 'albinism' is controlled by one gene and is recessive.
~B


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## josh raysin (Nov 28, 2005)

> But if you breed an actual albino to a regular frog, than all of the offspring will be 'het' for albino


 yes, but ive never read of an albino being bred with the exception of the vents. i was specifically referring to the ones being touted as het for albino. without being bred with an albino not all offspring will be hets for it.



> This also assumes that the trait 'albinism' is controlled by one gene and is recessive.


yes it is making the one gene assumption. btw albinism is always recessive.


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## josh raysin (Nov 28, 2005)

> By the way im selling an alanis thats het for albino its grandfather was albino


 how do you know its het for albino?
F1 AAxaa=all Aa, F2 AaxAa is what i went over in the first post.


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## xfrogx (Jul 5, 2006)

josh raysin said:


> > By the way im selling an alanis thats het for albino its grandfather was albino
> 
> 
> how do you know its het for albino?
> F1 AAxaa=all Aa, F2 AaxAa is what i went over in the first post.



its father's dad was albino and the mom's grandmother was albino. This would mean theres a 66% chance right? I may have misunderstood your post so let me know if this is what you were talking about. Thanks


ramsey


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## Michael Shrom (May 20, 2004)

You are correct. The add for het or albino frogs because the frogs grand parents were het or albino should read "possible het for albino". Their is a possibility the recessive gene was passed down genotypically without being phenotypically expressed. Their is a much better chance they are all normal genotypically. Of course this is assuming the albinism in this frog is a simple recessive. Lots of times albinism (lack of normal pigment) is simple recessive but some times it isn't.


I went to Millersville State but my salamanders went to Yale.


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## snmreptiles (Feb 26, 2004)

Josh and Michael are 100% right, the only way to get 100% hets, is to by breeding a homozygous animal to any other animal. If one of the parents isn't an albino, you should be selling it as a possible het. Any questions, check out this link... http://geneticswizard.com/

Mike
http://www.snmreptiles.com


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## snmreptiles (Feb 26, 2004)

The more I think about some things on this thread, the more I am confused...The first time I heard about albino alanis was less than two years ago, and they were just morphing out from normal parents...How on earth have their been 3 generations since then?? Not accusing anyone of anything, just a little confused!

Mike
http://www.snmreptiles.com


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## O2 Plastics (Jun 28, 2006)

I think the problem is just basic misunderstanding. Keepers of other herps have been playing with genetics for years and figuring odds for simple/double/dom/codom crosses are almost second nature. But new folks in those hobbies often make the same mistakes. I've lost track of the snake ads I've seen advertising het whatever from a het/normal cross. Admittedly some ads are posted by bad people taking advantage of the ignorant, but most are just mistakes.

For simple recessives quick and simple. 

With trait to With trait = 100% with trait

With trait to normal = 100% het. no visible trait

100% to 100% het = 66% het
- statistaclly 1 in 4 will have trait, 1 in 4 normal, 2 in 4 will be het

100% het to normal = 50% het

Anything past this IMO should be sold/considered normal unless it happens to prove out. It's not worth the time to worry about the "possible", the odds are too remote with all but the largest breeding groups.

Double hets follow the same guidelines, but the stats are 1 in 16 instead of 1 in 4.

Then you get into co-dom/recessive's and the math gets a little painful


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## zBrinks (Jul 16, 2006)

If you google "punnett's square", it should show how to figure out theoretical percentages of the offsprings' genotype. Btw, for you vocab nuts:

genotype: what the animal's genetic material encodes
phenotype: what the animal looks like

ie: An albino (aa) to a normal frog (AA) will produce offspring that are genotypically het for albinoism (Aa), yet phenotypically they appear normal.


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## Michael Shrom (May 20, 2004)

I've seen adds touting 66% het or 25% het. I guess this could be misleading. Either they are het or are not het. What is implied is that in this cross with a normal recessive gene you have a 66% chance of your animals being het or 25% chance of being het. If you are buying frogs that just have a chance of being het and frogs that might have skewed sex ratios You'll need a lot of frogs or good luck to come up with a het pair.


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## edwardsatc (Feb 17, 2004)

Based on the parental lineage given and _assuming_ that the maternal "grandfather" and paternal "mother" were homozygous dominant _and_ assuming autosomal recessive, the probability is 1:6 het for albinism:

1:2 probability for father
1:2 probability for mother
2:3 probability for individual in question

Apply the product method:

1/2 x 1/2 x 2/3 = 2/12 = 1/6


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## snmreptiles (Feb 26, 2004)

25% HET...HUH?? I can't figure out how on earth that's possible...Unless people think that by breeding a 50% het you get 25% het babies, which is pretty far off.

Also the 1 in 6 notion is off as well. If I understand the lineage correctly the grandfather was albino, so that means dad would be a het. Therefor all of his babies are 50% hets, meaning 1 out of every 2 should carry the gene for albinism. Going back any further than that on the mother's side is pointless in my oppinion, but in any case the mom could be a het (She would have been a 50% het). So if the story is correct (The timeline here is still totally screwing me up) the Alanis for sale is a 50% het for albino at the very least with an off chance of being 66% het.

What people don't realize is that the 50% and the 66% are chances of being het, they don't carry 2/3 of the gene, it's the chance that the animal has of carrying the gene. As someone else said, they either carry the gene or they don't, it's all a gamble when dealing with possible (50%), and probable (66%) hets.

Mike
http://www.snmreptiles.com


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## edwardsatc (Feb 17, 2004)

snmreptiles said:


> Also the 1 in 6 notion is off as well. If I understand the lineage correctly the grandfather was albino, so that means dad would be a het. Therefor all of his babies are 50% hets, meaning 1 out of every 2 should carry the gene for albinism. Going back any further than that on the mother's side is pointless in my oppinion, but in any case the mom could be a het (She would have been a 50% het). So if the story is correct (The timeline here is still totally screwing me up) the Alanis for sale is a 50% het for albino at the very least with an off chance of being 66% het.


Without going too far into genetics, you're missing the fact that AaxAa (immediate parents) leaves us with a 1:2:1 genotypic ratio - (homozygous dominant: heterozygous: homozygous recessive). We can leave out homozygous recessive since the frog is obviously not albino. That leaves us with a 2/3 chance that it is het. Factor this into the product and you get 1/6.



> What people don't realize is that the 50% and the 66% are chances of being het, *they don't carry 2/3 of the gene*, it's the chance that the animal has of carrying the gene.


I think most realize this. Probability is what we're dealing with, not fraction of a gene.


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## snmreptiles (Feb 26, 2004)

Hey Donn,

Your definition totally throws me off, and I don't get what you are saying...Granted I don't have a degree in genetics, and haven't studied it for 12 years in a class. What I do have is a working knowledge of this as I have been breeding reptiles consistently for the last 6 years. This year we produced albino mack snow leo's which is a co dom and recessive trait in the same animal. I believe I understand this through and through as unfortunately the odds get stuck in my head and i can think about nothing else. LOL

What I don't get is your 1/6. There's a 50/50 chance of mom being a het, if she is then you are breeding het to het giving you an albino and 3 normal looking offspring (2 are hets, one isn't 2/3 = 66%) theoretically out of 4.

If mom isn't then you are breeding a het to a normal, giving you all 4 normal looking offspring, 2 are hets 2 are not, meaning you have a 50% chance of getting a het.

Please explain to me what is 1/6 as I am dumb founded!!

Mike
http://www.snmreptiles.com


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## O2 Plastics (Jun 28, 2006)

edwardsatc said:


> Based on the parental lineage given and _assuming_ that the maternal "grandfather" and paternal "mother" were homozygous dominant _and_ assuming autosomal recessive, the probability is 1:6 het for albinism:
> 
> 1:2 probability for father
> 1:2 probability for mother
> ...


hmmmm....

grandfather listed as homozygous = het offspring so father would be het
mother listed as homozygous as well = 1/4 homozygous, 1/2 heterozgous, 1/4 normal. 

Remove the homozygous offspring leaves 3 possible traits, 2 of which are heterozygous. So out of the normal looking offspring each has a 66% chance of carrying the gene.

Just eyeballing the above, I think the product method would generate erroneous results, especially since the end result (2/3) is being factored back into the list itself.


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## Mantellaprince20 (Aug 25, 2004)

who here has the research to back that albinisim is caused by a single gene? or that what we are seeing in these frogs is even albinism at all. From what i have seen, many of the tincs only lose their blue coloration, which leaves them as hypomelanistic, not ablino's. Without knowing the genese involved(which we don't), you technically can't call any of the frogs HET for albinism. This is sure the longest post I have seen for something that no one here can back up because of the lack of research


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## snmreptiles (Feb 26, 2004)

Ed,

I'll try to do this without sounding like a complete jerk...The original post was discussing Albino Alanis...If you have seen this frog it is definately NOT missing just the blue...It's pink white and yellow. I realize you have "albino" Patricia, but that's not what was being discussed. Other than those two (Patricia and Alanis) I haven't heard of "albinism" in Tincs, have you?? 

From the info that we have had it's obvious simple recessive in the Alanis. Two different breeders that got their frogs from the same parents have produced albinos...Meaning that they have het for albino frogs. Any of the offspring from the albinos would WITHOUT doubt be hets, from the way they were produced the first time.

As far as research goes you are correct, there hasn't been any done on it from me, I would jump at the chance to work with some of the alanis if I could! However, you don't need to research anything to see whats going on with the Alanis!! Your Patricia could be something different, that I have yet to see a picture of, so I can't comment on it!

MIke
http://www.snmreptiles.com


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## Ben_C (Jun 25, 2004)

> From the info that we have had it's obvious simple recessive in the Alanis.


The color mutant 'patricia' also appears to be simple recessive.



> that I have yet to see a picture of, so I can't comment on it!


Hey mike,
sorry I'm so late, but as promised, here are two pictures of a mutant 'patricia' that recently morphed...



















This is the first one that has a little blue (see area near cloaca). I've morphed out quite a few of these that are completely lacking blue...

anyway, sorry to hijack the thread.
~B


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