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RESEARCHG enomic selection (GS) is based on the use of genomic information to predict the genetic value of phenotyped or nonphenotyped individuals (Heffner et al., 2009). It has been effectively used in animal (de Campos et al., 2015;Farah et al., 2016) and plant breeding ( Jarquin et al., 2016;Huang et al., 2016). This strategy seeks to exploit information from markers in linkage disequilibrium (LD) with chromosomal regions that control the traits under evaluation (Heslot et al., 2015). To best explore this information, the development of genotyping technologies continues to generate significant quantities of markers. However, as marker densities increase, collinearity also increases. Additionally, evaluating a large number of individuals and complex experimental designs may lead to infeasibility of computational analysis.To reduce the number of genomic variables maintaining information, markers can be rearranged in LD blocks, known as haplotype blocks (Cuyabano et al., 2014). Capturing epistatic interactions of nearby single-nucleotide polymorphisms (SNPs), improving estimates of alleles identical by descent, and reducing the number of tests in association studies (which leads to the reduction in type I error rate) are some advantages of using haplotypes. Besides, it infers groups of correlated genes and alleles,
ABSTRACTThe implementation of single-nucleotide polymorphism (SNP)-based genomic selection has demonstrated great predictive potential in plants. However, its application is sometimes limited to the biallelism of the marker. In this context, the use of haplotype blocks as multiallelic markers might improve genomic prediction. This study was performed to compare the predictive ability of Bayesian genomic prediction models using haplotypes (confidence interval and four-gamete), individual SNPs, and sets of SNPs selected according to haplotype construction. The use of haplotype matrices increased the predictive ability and selection coincidence with the phenotypic selection for the maize (Zea mays L.) breeding population. However, this was not observed for the rice (Oryza sativa L.) population, in which the use of the nonreduced SNP matrix was more efficient. Overall, the use of reduced SNP matrices did not lead to better predictive abilities. No difference was observed between the genomic prediction methods used. We found that the use of haplotypes has potential to increase predictive ability of genomic prediction in breeding populations of allogamous plants or plants with high multiallelism.