Me and a friend of mine had a disagreement about genetics yesterday. So I would much appreciate anything anybody could contribute to find the correct answer. And if it wouldn't be too much trouble, please mention any education recieved on the subject. For example I know some people have taken college classes on specifically genetics. Just for credibility purposes when me and him look over the responses.

My Arguement was that a hypo that is not a homozygous (super) hypo is technically a Heterozygous hypo. The reason being that it carries 2 different alleles from 2 different genotypes of parents. if you bred a normal "het" hypo to a normal wild type boa, the babies would get 1 allele from each parent. So the genotype of the hypo babies would be 1 hypo gene, and 1 normal gene. which is why if that "het" hypo baby was raised and bred to another normal wild type boa, the phenotype of the litter would be approximately 50% "heterozygous" hypos and 50% normal. As opposed to a homozygous hypo bred to a normal wild type, would produce a litter of 100% "heterozygous" hypos. Hence why a hypo het albino is called a DOUBLE-het sunglow.

My friend's side of the arguement was that the term heterozygous means that a normal looking snake carries a recessive gene. The gene just does not show in the snakes phenotype. And also argueing my point that F1 hypos are not considered a heterozygous hypo because heterozygous has to be referring to a recessive trait.

Very quickly, I have the definition of Heterozygous from the book Designer Morphs, by John Berry.

"Hetero means different. Having two different alleles for a genetically inheritable trait. Thus, although heterozygous snakes carry the gene or inheritable traits of the particular morph they represent, they look like the wild type. Some hets carry or show genetic markers but these are not always reliable. Designer morphs with multiple unmatched mutant allele pairs are referred to as double hets or even triple hets."

Now, my personal opinion, that definition is rather poor, but I had the book in front of me, and it gets the point across.

Nowhere in the defination of heterozygous is the word recessive ever used. Because it does not matter if a trait is recessive or not, it simply refers to the alleles being different, which can be caused from a co-dominant gene, dominant gene, or recessive.

Another thing I would like to mention, although me and him did not get this far into it yesterday, but I know his thoughts on it. Lets make it clear that co-dominant and dominant have NOTHING to do with being a homozygous (super) animal. I think that is a huge misconception in breeding boas that a lot of people do not know the truth.

Hypos are dominant. I hear people refer to them as co-dom because if bred to a normal boa, the litter would be 50%/50%. This is the wrong way of thinking. They are dominant because the phenotype of a "het" hypo looks almost identical to the phenotype of a "homozygous" hypo. If a "het" hypo was bred to a "het" hypo, the babies would be approximately 50% het hypos, 25% normals, and 25% "homozygous/super" hypos. It works on the punnet square the same as a recessive gene would. We can make an educated guess on how to distinguish which is which between "het" hypos and "homozygous", but until its proven through breeding, it is unknown for sure.

This is different from the Motley gene. The motley gene is co-dominant. This is because if a "het" motley was bred to another "het" motley, the phenotype of the homozygous form is jet black with black eyes, looking completely different than its sibling "het" motley. And breeding a "het" motley to a normal wild type boa, would produce 50% "het" motleys, and 50% normal boas.

The bottom line is these 3 points.....

- Heterozygous does NOT mean carrying a ressive gene, it means carrying 2 different alleles

- F1 Hypos are technically considered "heterozygous" hypos

- Hypos are considered a dominant gene, while motleys are co-dominant.

Can I please have the opinions/support of everybody else who knows anything about genetics and how they work? If I am wrong about all of this, please say so, but I think I've just about hit the nail on the head for most of it.

Also, a question for my own knowledge, generation hypos... how does it work? I am under the assumption that F1 x F1 = F2, F2 x F2 = F3, F3 x F3 = F4, and so on. is that correct? And what would be produced by breeding F4 to normal wild type? Im under the assumption of F1s would be the result. Any knowledge to this would be greatly appreciated.

Thanks in advance
Tony

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