Genetics Selection Evolution 2009, 41:36 http://www.gsejournal.org/content/41/1/36 tion failure may be due to a lack of true associations between the trait and marker but could also be caused by differences in SNP frequencies, different marker-causative mutation linkage phases, genotype-by-environment inter- actions or epistasis as well as sample size effects and the way the trait is measured. Nevertheless, for those associa- tions confirmed here, the additional validation instils confidence in using these markers in selection pro- grammes for improved meat quality. Competing interests The authors declare that they have no competing interests. Authors' contributions JLG carried out data analysis and drafted the manuscript. SCB participated in the design of the study and statistical analysis and helped draft the manuscript. CMcC partici- pated in the design of the statistical analysis and helped to draft the manuscript. 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