Effects of heritability and number of quantitative trait loci (QTL) on accuracy of genomic estimated breeding value

In comparison to traditional breeding methods, using genomic information causes considerable increase in response for selecting young animals which have no phenotypic records. Genomic selection refers to selection based on estimated breeding value (BV). The purpose of this study was to survey the effects of heritability of trait and the numbers of QTL on accuracy of estimating genomic BVs. For this reason, genome design and required population was done by computer simulation. The results of the effects of trait heritability on the accuracy of genomic BV estimation showed that the accuracy of genomic BV estimation of reference group via three strategies of trait heritability 0.05, 0.1 and 0.25 were 0.790, 0.827 and 0.876, respectively. Therefore, increasing the level of trait heritability increased the accuracy of estimated BV. In strategies for numbers of 4, 10, 20 and 40 simulated QTLs (in each chromosome) through the genome, the calculated accuracy in reference group was 0.813, 0.833, 0.826 and 0.798, respectively. Totally, with increasing the simulated QTL, the range of alterations of the accuracy was not significant. Also, the alterations of accuracy along the consecutive generations from 51 to 57 generation had a decreasing trend in all four strategies.