The Genetics and Linkage of Odd-body, a Mutant of the German Cockroach1,2

Abstract

Odd-body (Ob) , a dominant mutation in Blattella germanica (L.), is described. The Ob homozygotes are lethal, and postembryonic lethality occurs frequently among heterozygotes. The position of the Ob locus in the 10th linkage group was determined by 2 sets of 3-point crosses, each having one crossover region in common. These data indicate a gene sequence of bu-Ob-cv-y. Differences in interference values are interpreted in respect to possible centromere location. A factor causing increased crossingover in different, but adjacent, chromosome segments in males and females is postulated for one set of crossover data.