GENE NUMBERS AND GENIC VARIABILITY INCIONA INTESTINALISANDBRANCHIOSTOMA LANCEOLATUM

Abstract
The numbers of genes coding for various enzymes have been determined in C. intestinalis (Tunicata) in comparison with B. lanceolatum (Cephalochordata) using electrophoretic methods. Both species, generally, have identical gene numbers for homologous proteins. The hypothesis that Branchiostoma represents an anciently polyploid step relative to Ciona is not supported. High levels of allozymic variation were observed in the 2 species. The data are discussed in view of the neutral mutation hypothesis.