Resources:
Genetics home resource (free download) -- Handbook - Genetics Home Reference
Charles Pritzel's Genetics For Herpers (not a free download) -- Genetics For Herpers: The Reptile and Amphibian Breeder's Guide to Genetics: Charles Pritzel: Amazon.com: Books
The genes are equivalent to the direction sheet in our Bild-A-Snake kit. There are actually two copies of the direction sheet. That makes two copies of each individual step. This is equivalent to a gene pair. If the two copies of a single step are the same, then the pair is homozygous. That direction is followed. However, the two copies may not be the same. Then the pair is heterozygous (het). If one copy of the step is in bold type and the other is not, then the bold type version is done. If both copies are in italic type, then both are done. (That may result in an intermediate appearance between results from when there are two copies of one or the other.)
The bold type is for the dominant gene, the non-bold type is for the recessive gene, and the italic type is for codominant genes. Clear as mud so far?
Each of the direction sheets has over twenty thousand individual steps. If we take a number of the sheets and compare a single step over all the sheets, then most copies of that step will be the same. That is the equivalent of the normal gene AT THAT STEP. The normal gene at one step is not the same as the normal gene at a different step. But each is the most common gene at its own step. A gene that is not the most common at its step is a mutant gene.
A snow boa has two gene pairs containing mutant genes. One gene pair has two albino mutant genes. The other gene pair has two anerythristic gene pairs. All the other gene pairs have two copies of the normal gene for that step. For convenience, we ignore the gene pairs that contain two copies of the normal gene.
A salmon albino anerythristic (AKA moonglow) boa has three gene pairs of interest:
gene pair 1 = a salmon (AKA hypo) mutant gene and a normal gene
gene pair 2 = two albino mutant genes
gene pair 3 = two anerythristic mutant genes
A salmon, het albino, het anerythristic (AKA triple het moonglow) boa also has three gene pairs of interest:
gene pair 1 = a salmon (AKA hypo) mutant gene and a normal gene (produces the salmon appearance)
gene pair 2 = an albino mutant gene and a normal gene (no change from normal appearance)
gene pair 3 = an anerythristic mutant gene and a normal gene (no change from normal appearance)
Herpers do not do a good job of distinguishing between the genes in a gene pair and the change from the normal appearance that the mutant genes produce.
Here are some tips for a single gene pair:het = the gene pair is made up of a dominant normal gene (not named) and a recessive mutant gene (named). Example -- a het albino boa has a gene pair made up of a normal gene and an albino mutant gene. Appearance is no change from the normal appearance.
visual het = the gene pair is made up of either a recessive normal gene and a dominant mutant gene or two codominant genes. In both cases, the snake does not look normal.
super = the gene pair is made up of two copies of either a dominant mutant gene or a codominant mutant gene.
Hope this will help. I must logout, but questions are always welcome.
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