Posted by:
prehistoricpets
at Sat Apr 5 19:19:00 2008 [ Email Message ] [ Show All Posts by prehistoricpets ]
Technically what we call "Co-dominant" in reptiles is incomplete dominant.
Here are some definitions:
In codominance, neither phenotype is recessive. Instead, the heterozygous individual expresses both phenotypes. A common example is the ABO blood group system. The gene for blood types has three alleles: A, B, and i. i causes O type and is recessive to both A and B. The A and B alleles are codominant with each other. When a person has both an A and a B allele, the person has type AB blood.
When two persons with AB blood type have children, the children can be type A, type B, or type AB. There is a 1A:2AB:1B phenotype ratio instead of the 3:1 phenotype ratio found when one allele is dominant and the other is recessive. This is the same phenotype ratio found in matings of two organisms that are heterozygous for incomplete dominant alleles.
Incomplete dominant
Discovered by Karl Correns, incomplete dominance (sometimes called partial dominance) is a heterozygous genotype that creates an intermediate phenotype. In this case, only one allele (usually the wild type) at the single locus is expressed in a doseage dependent manner, which results in an intermediate phenotype. A cross of two intermediate phenotypes (= monohybrid heterozygotes) will result in the reappearance of both parent phenotypes and the intermediate phenotype. There is a 1:2:1 phenotype ratio instead of the 3:1 phenotype ratio found when one allele is dominant and the other is recessive. This lets an organism's genotype be diagnosed from its phenotype without time-consuming breeding tests.
Example of Co-dominant would be
Sharp Albino X Boa Woman Caramel = Normals, hets for one morph or the other and Paradigms.
Incomplete Dominant would be
Tiger X Tiger = Normal, Tiger, Super Tiger.
Per my understanding, an incomplete dominant trait would express itself in one of two ways. 1.) Visual Heterozygous with one affected Gene. 2.) Visual Homozygous with two affected Genes.
Time will tell what's going on with this morph. Either way it keeps it fun!
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RE: Incomplete Dominance... - prehistoricpets, Sat Apr 5 19:19:00 2008