No need to get lost, just remember that the reference is always to the wild-type allele.
What if you have the albino locus where there's this:
· Normal (Dominant to amel and ultra, codominant with hyper)
· Amelanism (Recessive to normal, dominant to hyper, codominant with ultra)
· Ultra (Recessive to normal, codominant with amel, codominant with hyper)
· Hypermelanism (Codominant with normal, recessive to amel, codominant with ultra)
How would you indicate all of those relationships with simple symbols?
It would be nice if that could be incorporated into a simple symbology, where you could tell how every allele related to all others just by comparing symbols. But I don't think it's very practical, and I've never seen one used before. The trick is that there are going to be loci where there are plenty of mutant alleles. At the albino locus in mice, there are six or seven mutants, plus the wild type. Some alleles can be dominant, codominant, and recessive, depending on which other allele you are comparing it to, so the default reference is to the wild-type since there is always a wild-type.