We have observed unusual dominance/recessive relationships
with severe alleles of abi3, which pleiotropically affect Arabidopsis
seed development. For a given abi3 allele, some phenotypes are
dominant to wild-type while other phenotypes are recessive to the
same wild-type allele. Dominance is therefore a property of the
phenotype rather than a property of the allele. It is very difficult to
see how this situation can be clearly represented with allele symbols,
because the dominance relationship is not a property of the allele, but
of the way dominance is assessed (i.e. how you analyze the phenotype).
If this situation turns out to be a general case, using allele
designators to indicate dominance could result in catastrophic
Has anyone else observed this sort of situation?
Kallie Keith keith at gpu.utcc.utoronto.ca
Peter McCourt peterm at gpu.utcc.utoronto.ca