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I've just started venturing into the boa morphs, been into colubrids for years, I am somewhat confused with the Salmon DH Sunglow versus the Salmon Het-Albino terminology!

I know Salmons are Co-Dom and Albinism being recessive BUT what does the Double Het stand for in the Salmon DH Sunglow (I would think double recessive Hypo and Albino) But the Salmon is co-dom and this might be throwing me off? Is there a recessive Hypo part of this?

Isn't the proper terminology Salmon Het-Albino for Sunglow project boa's

Thanks in advance for clearing that up for me.

You got it right, there is no recessive hypo gene. However, hypo is het for super hypo, so in a way, it is a double het. But hypo het albino is more correct.

Matt Cabe

There's really NO SUCH THING as a "co-dominant" hypo,(regarding the currently accepted "salmon & orange-tail hypos".)The trait is dominant,nothing "co-",or,"incomplete" about it. when the original breedings were done,it was obvious that the trait was NOT recessive,but,the reasoning was,(at the time.) "if it WAS dominant why were only half the babies hypos???...in an effort to describe the trait,and,it's behavior,these terms (co-dominant & incomplete dominant.)were adopted prior to a full understanding of it. I simply believe that those initial breedings were done using heterozygous animals,which naturally resulted in a 50/50 split,(same result as breeding a recessive het to a non-gene carrier,the difference being,of course,that with dominant traits the heterozygous animals CAN be distinguished from the "normals",so we don't use the "50% possible het" term.)so the term double het for sunglow is perfectly acceptable,(if,in fact the hypo expression is in its heterozygous state.)in the near future we will see double homozygous sunglows...unfortunately many people think that heterozygous is synonomous for "something you cannot see"...it ISN'T,it simply means that the genetic trait in question is in its intermediate form,or,state of being....the term heterozygous is not exclusive to recessive traits only.

I've looked at the Ihle, et al., paper about salmon in the Journal of Heredity. They found homozygous salmons that did look different from the heterozygous salmons. The assumption was that ALL homozygous salmons were visibly different from ALL heterozygous salmons. That assumption has turned out not to be true, so salmon should be called a dominant mutant gene.

The definition of heterozygous is a pair of genes that are not the same. They could be a normal gene paired with a mutant gene, such as a normal gene paired with the albino mutant or a normal gene paired with the salmon mutant. Or they could be two different mutant genes, though I am not aware of a case of multiple mutant alleles in boa constrictors yet. Check the definition on www.dictionary.com. Anyway, the appearance of the heterozygous animal determines whether a mutant gene is dominant, codominant, or recessive to the normal gene.

If you mate two heterozygous salmons together, all the normal-looking babies are genetically normal. And all the salmon babies are salmon, 66% probability heterozygous salmon (or 33% probability homozygous salmon).

Strictly speaking, as there is no gene named sunglow, and "heterozygous" only refers to the genes, there is no such thing as het (or double het) for sunglow. IMHO, "salmon, heterozygous albino" is the best way to describe such snakes.

Paul Hollander