A second multivariate analysis (to investigate the effect of Day 7 embryo size on the Day 7 gene expression) indicates an effect of embryo size on the gene expression profile (P = 0.01, i.e., gene expression profile is predictable based on embryo size). A high level of correlation structure (R = −0.6 to 0.9) was detected in the gene expression data (Supplemental Figure S12, https:// doi .org/ 10 .3168/ jds .2017 -14306; for the 81 genes with gene expression greater than the limit of detection of the assay, yellow denotes high positive correlation between genes in the estimated error variance-covariance matrix Σ in Equation [6]).