Abstract
A new variant of glucose phosphate dehydrogenase was discovered in rat erythrocytes and shows autosomal dominant inheritance. The locus, provisionally denoted Gpd, is closely linked to catalase (Cs-1), and there is some evidence that these loci may be assignable to linkage group II. Also in linkage group II, Pgd (6-phosphogluconate dehydrogenase) was found to be linked to b (brown). The linkage between Pgd and b permits linkage group II to be assigned to chromosome 5.