Effects of Selection and Linkage on Degree of Inbreeding

Abstract

Monte Carlo computer techniques were employed to simulate inbreeding in small populations under regimes consisting of combinations of three degrees of linkage and three intensities of selection. Selection and linkage each significantly increased the rate of inbreeding in populations of a given size, although the effect of linkage was larger. Linkage contributions to bias in the coefficient of inbreeding may exceed those of selection in general, if one restricts comparisons to levels of the two factors that are similar with respect to the range of their possible values. Linkage also had a much larger effect than did selection on inflation of the variance of estimates of the coefficient of inbreeding. The joint effects of selection and linkage can have severe implications with respect to inbreeding in artificial selection programmes.