The evidence of a null allele in the esterase D in the Polish population.

The existence of the allele EsD degree in mother and her child, expressed phenotypically as EsD 2-0 and EsD 1-0 has been found. The enzymatic activity was reduced to about 50 per cent of the normal values of these phenotypes.

Rare alleles of phosphoglucomutase (PGM1) in the Polish population.

Phenotypes of the erythrocyte enzymes phosphoglucomutase (PGM1) were determined by horizontal starch gel electrophoresis in south part of Poland. The gene frequencies were calculated: PGM1(1) = 0.73526, PGM2(1) = 0.