alpha-1-Antitrypsin (Pi) polymorphism in Serbia: deviation of Pi M subtype distribution from the Hardy-Weinberg equilibrium.

ABSTRACT

The distribution of the alpha 1-antitrypsin (Pi) phenotypes and subtypes was investigated in a population sample of 1060 unrelated individuals from Serbia (Yugoslavia). The allele frequencies estimates were Pi*M1 0.702; Pi*M2 0.183; Pi*M3 0.088; Pi*Z 0.013, Pi*S 0.007; Pi*P 0.004; Pi*F 0.003. The observed phenotype frequencies differed very significantly from those expected assuming H.W. equilibrium (chi 2 = 49.51, p < 0.0005). The deviation from equilibrium involved the three Pi*M subtypes an excess of Pi*M1, Pi*M2 and Pi*M3 homozygotes was found, with the corresponding decreased number of M1M2 and M1M3 heterozygotes. The possible significance of this finding is discussed.