With three different SNPs each with two possibilities (wild type or mutant), there are a total of eight possible variants on a chromosome for the gene TAS2R38. Two of these variations are especially common. First, the so-called AVI allele (if this variant is homozygous, thus appearing on both chromosomes, certain bitter substances can only be perceived poorly); secondly, the PAV allele (if this variant is homozygote, the bitter substance can be perceived even in low concentrations). Basically the genotypes can be divided into three major groups. First, there are the people who are designated as Non-tasters. They possess the AVI allele homozygote, which means on both chromosomes. The second group is the Super-tasters, who have the PAV allele on both chromosomes. The third group represents the Tasters. These have either the PAV and the AVI allele or less common variants.

About 77 percent of our examined DNA samples could be assigned to three major types. The rest of 22.8 percent was divided into 10 rare variants (homozygotes, heterozygotes), which could also be counted as a Taster type. It should be noted that we could not determine on which chromosome which variant lies for the heterozygous types.

In further analysis, it is also interesting to us how the wild types and mutants are distributed within the SNPs (Table 1). We recognized that with each SNP, the distribution between wild type, mutant and heterozygous forms are very similar.

A more detailed analysis of the evaluation, particularly in connection to the data of the sensory tests, can be found in chapter 7.

Table 1: Distribution of wild type and mutants in individual SNPs