PREDICTION OF THE POWER OF DETECTION OF MARKER-QUANTITATIVE TRAIT LOCUS LINKAGES USING ANALYSIS OF VARIANCE

Analysis of variance can be used to detect the linkage of segregating quantitative trait loci (QTLs) to molecular markers in outbred populat ions. Using independent full-sib families and assuming linkage equilib rium, equations to predict the power of detection of a QTL are describ ed. These equations are based on an hierarchical analysis of variance assuming either a completely random model or a mixed model, in which t he QTL effect is fixed. A simple prediction of power from the mean squ ares is used that assumes a random model so that in the mixed-model si tuation this is an approximation. Simulation is used to illustrate the failure of the random model to predict mean squares and, hence, the p ower. The mixed model is shown to provide accurate prediction of the m ean squares and, using the approximation, of power.