Abstract
A deficiency of the normally prominent alkaline phosphatase zone (by starch-gel electrophoresis) has been discovered in a newly investigated laboratory strain of Drosophila melonogaster. Mating experiments indicate that genetic control is by an allele of a previously described electrophoretic variation. Heterozygotes resulting from crosses of the deficient type and the fast electrophoretic variant show only the fast phenotype. In deficient x slow heterozygotes, however, there is a new band that does not correspond in electrophoretic mobility with any of the bands of other heterozygous or homozygous types. It is suggested that the allele responsible for the deficiency leads to the manufacture of an inactive subunit that is able to hybridize with the subunits of the slow electrophoretic form.
