I don't understand why dominant traits are not always the most common traits?
If anyone can explain this, I would appreciate it!
Let's say the gene responsible for eye colour has four different alleles, green (g), blue (bl), brown (br) and black (B)
The only way you can be sure if an allele is dominant is when you actually compare it to other alleles. So black in this case is dominant and the eye colour will be black if even one of eye colour alleles is black.
However, you don't know whether green is more dominant over blue or brown, whether brown is more dominant over green or blue and whether blue is more dominant over brown or green.
If blue happens to be dominant over green then you'd express it as Blg,etc.
This is an example of the fact that one allele will always be dominant over the other. And the question will always provide you with this information. Unless they ask you to figure it out using a test cross.
That's why you'd never express a heterozygote with green and blue alleles as blg because one always has to be dominant over the other or both have to be dominant which will be a case of co-dominance- the expression of both alleles which both happen to be equally dominant.
Hope this helps
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