The Hardy-Weinberg principle is used to characterize the distribution of the different genotype frequencies in a population which are not evolving. In the Hardy-Weinberg equation,
the frequency of the homozygous dominant genotype is denoted by ;
the frequency of the homozygous recessive genotype is denoted by ;
the frequency of the heterozygous genotype is denoted by 2pq;
the frequency of the recessive allele is denoted by q;
the frequency of the dominant allele is denoted by p.