I am going to rephrase your question (explained next paragraph, and to align it with the my answer...) ; what causes the partial*translucent & hypo polygenic phenotype?
I have theories, but limited experience with the translucent mutation (not a big fan, I have produced less than 100) and zero experience breeding "partials"
I have not produced a translucent from monogenic parents (trans without the hypo factor) so I cannot comment on the trans-only portion of your question.
Epistasis: A lot of genes work independent of each other, but sometimes one gene cannot function without the presence of an independent gene (the two genes don't do anything together, but one gene needs another gene for expression). [example: gene
a suppresses certain chromatophores *pigment containing and light reflecting cells*, and gene
b dictates the distribution of gene
A (gene
a does not need gene
b , and if gene
B was missing from the genotype then that dragon may appear patched, or partial translucent] This would imply more than one gene affects the overall outcome of the phenotypes expression. Quantitative inheritance. (not using polygenic here (and I really could) because the expression of the traits may not be influenced by two different phenotypes, still they are two genes). QI and polygenic are essentially the same, actually they are, but for simplicity I use QI and polyg separately.
Repression (molecular genetics): a DNA Binding protein (repressor) that blocks phenotype expression to varying degrees. My understanding of molecular genetics is vague, and I have almost no research backing this theory. Basically the body tries to put a stop to the gene.
Multiple allele: Every diploid organism inherits 1 allele from each parent for each gene. Each gene is made up of a pair of alleles. Alleles are found on the loci (specific location) of a chromosome, and some loci can have multiple alleles that can each affect the outcome of a gene. If multiple alleles are present then the phenotype may be expressed differently depending on which allele is selected during chromosomal crossover. However, multiple allele conditions
often result in no change of the phenotype, no matter which allele is selected during chromosomal crossover.
Polygenic: Simply put a polygenic trait is a phenotype of two or more separate genes. Hypo and translucent when combined is a polygenic trait because the phenotype is made up of two *or more* genes. Significant variations of the typical hypo trans phenotype can occur at the allele level as the certain characteristics
can be drastically changed by certain alleles that make up the gene. Polygenic is a bit of Mendel principal, multiple alleles and a pinch of epistasis. (lol, nerd joke, really not funny in hindsight.)
This is theory, loose theory, feel free to debate, I would like to advance this topic and a group discussion will certainly help
All alone out here.
By the way M.F., I hit all of your topics so we won't have to do this on the phone tomorrow. LOL.
