The localization of ALDH1 to a fraction of WT blastema cells but not to the undifferentiated blastema of the human foetal kidney (located in differentiated structures), indicates that ALDH1 is likely to be associated with stem cell activity and CSCs, similarly to other cancers (Ginestier et al, 2007; Ma et al, 2008; Pearce et al, 2005; Silva et al, 2011), rather than being a specific renal lineage blastema marker (Metsuyanim et al, 2009; Roth et al, 1988a, b). Here, ALDH1A1 is linked to cancer.