In contrast, ALDH+ derived tumours had a mixed phenotype, where 20–40% of the melanoma cells did not show ALDH activity, whereas remaining 60–80% staid ALDH positive (Figure 4, right branch, n = 7) This confirms higher abilities of the ALDH+ cells to reestablish tumour heterogeneity, i.e. the existence of “cellular hierarchy” with respect to ALDH. This evidence concerns the gene LDHA and neoplasm.