Principal components analysis. (A) The top three principal components of all 158 samples from all of the 19 organs. Cerebellum, cerebrum, heart, skeletal muscle, liver, and testis clustered separately from the rest of the organs (gray color). (B) After the above six organs in A were removed, PCA was recalculated with the samples from the remaining 13 organs. Adrenal, kidney, pancreas, lung, and spleen clustered separately from the rest of the organs (gray color). (C) After the above five organs in B were removed, PCA was recalculated with the samples from the remaining eight organs (ovary, prostate, bladder, colon, ileum, stomach, ureter, and uterus). (D) Cerebrum, cerebellum, heart, and skeletal muscle were separated completely with recalculated PCA.
