Interloci equilibrium between pairs of gene markers in the samples of different health rate in the population of Buryats of Chitinskaya Province was tested. The following methods were used: calculation of interloci correlation coefficients, chi 2-testing of the hypothesis of interloci equilibrium and the modification of principal components analysis on the basis of the matrix of Pearson's coefficients of contingency. In the groups of "extreme" health rate the tendency to increase in interloci disequilibrium was discovered. The reason for this effect is the increase in some phenotype combination frequencies that can be considered as markers of non-specific individual resistance in the environmental condition of the populations studied.