Isoelectric focusing of human red cell phosphoglucomutase (PGM1). Phenotype distribution in the population of Tuscany and two hereditary variants.

Phosphoglucomutase (PGM1) phenotypes were determined in a population sample of Tuscany, Italy, by isoelectric focusing. The frequencies observed for the four alleles are: PGM1+1 = 0.6012, PGM1-1 = 0.1059, PGM2+1 = 0.2495, PGM2-1 = 0.0434. Two variants were detected and it was possible to study the parentage of both of them. The pedigree of the propositus of the first variant shows that the variant occurs in combination with the common alleles PGM1 1+ and PGM1 2+ and that it has an autosomal dominant inheritance. The second variant has been shown to be a product of the PGM2 locus, although its PAGIF pattern is included between 2- and 1+ isoenzymes.