Selective structure of the gene pool: III. Estimation from F-ST-statisticswith the use of numerical resampling

The selection pressure on the ith gene was determined on the basis of the h eterogeneity of interpopulation diversity F-ST(i), assumptingn that the sig nificant deviation of F-ST(i) (observed differentiation of the ith gene) fr om F-e (selectively neutral differentiation) indicates selection. A selecti vely neutral variation F-e was estimated from the mean (F) over bar(ST). av eraged over the total set of genes. Since the validity of the equation (F) over bar(ST) approximate to F-e = (4 (N) over bar(e)M(e) + 1)(-1) depends o n the fulfilment of conditions of the theoretical model as well as on organ ization of sampling of genes and subpopulations rather than on statistical parameters of the gene sample, an additional correction by boot-strapping i s suggested. Simulation of sampling of the gene pool using numerical resamp ling (10(6) samples from each of the 50 markers) allowed us to characterize the selective structure of the gene pool. This structure consists of the f ollowing: one class of selectively neutral genes, NEUTRAL (F-ST(i) approxim ate to F-e); and two classes of selective genes, LOWER DIFF (F-ST(i) < F-e) and SUPER DIFF (F-ST(i) > F-e) Interclass regions N-LOWER and N-SUPER betw een the classes of neutral and selective genes were defined with the use of bootstrapping. The hypothesis on the presence or absence of selection cann ot be formulated with regard to the genes included in the interclass region s. A general trend for all gene pools of the world was revealed: the ratio between the boundary values of selective classes and F-e is constant. On th e basis of this, a rapid and simple technique for estimating selective valu es of genes was developed. The positions of more than 80 immunobiochemical gene markers in the selective structure of six gene pools of the world (Eur ope, Asia, Africa, Australia, America, and northeastern Eurasia) are presen ted. The selective structure of five subregions of northeastern Eurasia (Ca ucasus, Europe, Ural, Siberia, and Central Asia) are characterized as well.