The term genotype x environment (GxE) interaction describes the variation in phenotypic response of specific genotypes to specific environments (Lynch & Walsh, 1998), i.e. genotypes are differently affected by different environments. Significant GxE interaction can result in scaling effects, linked with heterogeneity of genetic variance in different environments, and in re-ranking of genotypes due to their genetic value in different environments. Ignoring GxE interaction in the context of breeding value estimation can thus lead to suboptimal selection decisions given that selection is for a different environment than the one the trait is measured in. While scaling effects only causes problems when breeding indices are built from various traits (Dominik & Kinghorn, 2008), re-ranking of individuals leads to suboptimal selection decisions.