Electrophoretic and heat-stability polymorphism at the phosphoglucomutase (Pgm) locus in natural populations of Drosophila melanogaster.

Genetic polymorphism for electrophoretic and heart-sensitive alleles is known at the phosphoglucomutase (Pgm) locus in Drosophila melanogaster. Analysis of the distribution of electrophoretic and thermosensitive (ts) alleles was carried out in natural populations from Canada and West Africa and compared with already known data on Italian populations [Trippa, G., Loverre, A., and Catamo, A. (1976). Nature 260:42]. The data show the existence of five common alleles, Pgm1.00,tr, Pmg1.00,ts, Pgm0.70,ts, Pgm1.20,ts, and Pgm1.50,tr, and two rare alleles, Pgm0.55,ts and Pgm1.20,tr. The most frequent allele is always Pgm1.00,tr; the second most common allele is always of the ts type. The cumulated frequencies of ts alleles in the populations varies between 11 and 32%. The heat stability polymorphism is present in all populations examined and shows again the uniform geographic pattern that has been found for electrophoretic variation at this locus.