The paraoxonase polymorphism in a Saudi Arabian population

The paraoxonase polymorphism was analysed in the serum of 248 individuals from Saudi Arabia. The phenotyping method used was one based on the ratio of paraoxonase/arylesterase, described in earlier studies. The distribution of this ratio in the sample was trimodal and it provided a good resolution for the identification of three phenotypes: A-homozygotes with low activity; B-homozygotes with high activity; AB-the corresponding heterozygotes, with intermediate activity. Gene frequencies were 0.7296 for the allele A with low activity and 0.2704 for the allele B with high activity. These frequencies are close to those observed in Caucasian samples from North America and Europe. Phenotypic frequencies in the sample fit the Hardy-Weinberg equilibrium.