Hidden Alleles at the Alpha-glycerophosphate Dehydrogenase Locus in Colias Butterflies

By varying polyacrylamide gel pore size, the alpha-glycerophosphate dehydrogenase locus of Colias butterflies is shown to contain at least five alkeles, rather than the two which had been reported previously. Two of the alleles have the same apparent net charge, and presumably are detected electrophoretically because of the conformational differences. Additional variation occurs in the isoelectric points of the proteins. It is suggested that electrophoresis employing a single gel of intermediated pore size will fail to discriminate between many alleles, and that the concept of electrophoretic alleles as differing simply in charge may not always be appropriate.