Phosphoglucomutase polymorphism in Swedish horses

Summary Polymorphism of phosphoglucomutase (PGM) in horse erythrocytes was studied by means of starch gel electrophoresis. Three different phenotypes, F, FS and S, were found. Family data supported the genetic theory of two autosomal, codominant alleles PGMF and PGMS controlling the variation. The gene frequencies were estimated to 0.28 and 0.72, respectively, in the North-Swedish Horse breed and to 0.13 and 0.87, respectively, in the Swedish Trotter Breed. The probabilities of excluding a falsely assigned stallion in the PGM system were calculated to 0.16 and 0.10, respectively, in the two breeds.