The occurrence of PGM1 phenotypes in 589 samples from the population of Padua was investigated by ultrathin-layer isoelectric focusing. All ten phenotypes were observed. Frequencies of the PGM1 alleles (1+ = 0.6180; 1- = 0.1163; 2+ = 0.2122; 2- = 0.0535) have been compared to those found in other populations.