GPT polymorphism in the Polish population.

In a sample of the Polish population numbering 703 subjects, three GPT types were encountered with the following frequencies: GPT1-1 0.265, GPT 2-1 0,509 and GPT 2-20.226. Frequencies of GPT1 and GPT2 genes were 0.519 and 0.481 respectively. Distribution of types in 217 mother-child pairs and in 12 families with 36 children was consistent with the hypothesis that the GPT system is dependent on a pair of codominant alleles and confirms that the GPT 1-1 and GPT 2-2 types are homozygotes, and GPT 2-1 is a heterozygote.