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Yep...another question... Are heterozygous albinos phenotypes normal or albino? I read the responses to a similar question below and am still not too sure I undterstand how the genetics work...

It appears that Albino is completely recessive and the hets are indistinguishable from the normal for albino genotype.

The heterozygous phenotypes are normals. Simply put.

Phenotype is thier physical appeareance.

Whereas genotype would be thier genetic makeup.

If you breed 1.1 100% Het Albinos

Doing the punnett square-

where A is normal and a is albino.
_____________
____|Aa__Aa__|
-Aa-|AA-|-Aa |
-Aa-|Aa-|-aa |
_____________|

The genotype would be:

25% Dominant homozygous, - AA - Normal
25% Dominant Recessive, aa - albino.
50% Heterozygous - Aa het albino.

I am pretty sure this is correct.

If anyone wants to elaborate, feel free, as well as correcting me.

Joel

>>Yep...another question... Are heterozygous albinos phenotypes normal or albino? I read the responses to a similar question below and am still not too sure I undterstand how the genetics work...
-----
- Joel Smith

"If you're not part of the solution, you're still part of the problem"

--

"Heterozygous Phenotype" is sort of a mixed up term.

Phenotype appears to the appearance of the animal, i.e. whether it looks normal or not.

Genotype refers to its genes, whether it is homozygous normal, heterozygous mutant, or homozygous mutant.

Depending on the inheritance of the mutation, heterozygous genotypes may or may not have a normal phenotype.

With purely recessive mutations like albino the heterozygous albino genotype results in a normal phenotype.

With the co-dominant or incompletely dominant mutation pastel the heterozygous genotype results in the pastel phenotype and the homozygous mutant genotype results in the super pastel phenotype.

So, don't fall into the trap of always thinking "het" = "normal looking" just because that is how it works out with the recessive mutations you learned about first. Remember that heterozygous and homozygous refer to the genotype and you must know the mutation type to then correlate to the phenotype.

>>"Heterozygous Phenotype" is sort of a mixed up term.
>>
>>Phenotype appears to the appearance of the animal, i.e. whether it looks normal or not.
>>
>>Genotype refers to its genes, whether it is homozygous normal, heterozygous mutant, or homozygous mutant.
>>
>>Depending on the inheritance of the mutation, heterozygous genotypes may or may not have a normal phenotype.
>>
>>With purely recessive mutations like albino the heterozygous albino genotype results in a normal phenotype.
>>
>>With the co-dominant or incompletely dominant mutation pastel the heterozygous genotype results in the pastel phenotype and the homozygous mutant genotype results in the super pastel phenotype.
>>
>>So, don't fall into the trap of always thinking "het" = "normal looking" just because that is how it works out with the recessive mutations you learned about first. Remember that heterozygous and homozygous refer to the genotype and you must know the mutation type to then correlate to the phenotype.
-----
- Joel Smith

"If you're not part of the solution, you're still part of the problem"

You are on everywhere except this:

>The genotype would be:
>
>25% Dominant homozygous, - AA - Normal
>25% Dominant Recessive, aa - albino.
>50% Heterozygous - Aa het albino.

It should be as follows:

25% homozygous wild type, - AA - Normal phenotype
25% homozygous recessive mutant, - aa - albino phenotype
50% Heterozygous - Aa het albino, normal phenotype.

Homozygous = the two members of a gene pair are the same.
Heterozygous = the two members of a gene pair are different.

There is no such thing as "dominant recessive".

Paul Hollander

I've got some detailed info on simple recessive inheritance, as well as punnett squares shown for all of the possible combinations. Let me know if you have any questions....
Joe Pociask Pythons - Genetics