A) Principle component analysis (PCA) plot of variance stabilized gene expression of engineered heart tissues (3DCT), adult heart left ventricle tissue, and other adult tissues from the Genotype Tissue Expression (GTEx). B-E) PCA plots of variance stabilized gene expression across engineered heart tissues, adult heart, and fetal heart for cardiac-specific genes: calcium-handling genes (B; 10 genes), conduction genes (C; 10 genes), energetics genes (D; 6 genes), maturation genes (E; 4 genes).