Alpha-1-proteinase inhibitor gene frequencies in Belgium

The alpha-1-antitrypsin phenotype was determined in cord blood of 1345 Belgian newborns by isoelectric focusing in polyacrylamide gels. Proteinase inhibitor (PI) gene frequencies were calculated. The relative gene frequency of the M allele was 0.9245, and those of S and Z alleles were 0.0543 and 0.0167 respectively. I and F alleles were less represented. These results are in agreement with population studies of neighbouring countries.