Abstract
Genetic studies of the Bombyx mori Kiuki mutant were made on the segregation of the F2 and BF1 phenotypes. Assay of sepialumazine in these phenotypes revealed that the Kiuki mutant is an incomplete dominant. A symbol Sel is given to the mutant gene. Enzymatic studies on F2 progeny showed that the yellow larval integument colour characteristic of the mutant, which is due to accumulation of sepialumazine, is dependent on the activity of sepiapterin deaminase. Linkage test showed that the Sel is independent of the so far established 23 linkage groups but represents one of the still unknown group among remaining five chromosomes.
