TABLE 1

Joint frequencies of the nine genotypes for two loci, each with two alleles, A and a at locus A and B and b at locus B. These genotypic frequencies are expressed in terms of their single-locus genotypic frequencies and zygotic associations

Locus B
Locus ABBBbbbTotal
AA
Aa
Aa
Total1
• The possible values of zygotic associations are constrained by the single-locus frequencies such that only four of the nine zygotic associations need to be defined and the remaining five are entirely expressed in terms of the four defined zygotic associations. For example, if the zygotic associations for four double homozygotes, ωABAB, ωAbAb, ωaBaB, and ωabab, are defined, then the zygotic associations for the remaining five genotypes are expressed as follows: , and .