A computer method of detecting interacting DNA loci by constructing a contingency table from samples of a first trait and samples of a second trait. The samples of the first and second trait are associated with one of a plurality of genotype calls, each relating to an interaction between multiple DNA loci. The contingency table includes frequencies of each genotype call in the samples. Based on the contingency table, measuring the association between the plurality of genotype calls and the first and second traits. Classifying the genotype calls into a first group that is statistically associated with the first trait and a second group that is statistically associated with the second trait.