Heterosis in the codominance model: electrophoretic studies of proteins in the chicken-quail hybrid.

1. Electrophoretical comparisons was carried out on qualitative and quantitative differences of three proteins in the cock-quail hybrid: albumin, immunoglobulin and hemoglobin. All three components correspond to situations of codominance. 2. Heterosis was demonstrated twice: the immunological potentialities of the hybrid are increased by its possession of two types of Ig G; the affinity of hemoglobin for oxygen can be better regulated in the hybrid than in both parental species. 3. Proportions of the codominant parental components in the hybrid are different in the case of the three investigated proteins; this fact probably reflects the relative importance of the quantitative regulation of gene products in the hybrid.