EZH2 was initially identified as a homolog of the drosophila Enhancer of Zeste through exon trap screening of chromosome 21. Both EZH2 and the related protein EZH1 can form complexes with the noncanonical Polycomb repressive complex-2 (PRC2) and maintain repressive chromatin, but the PRC2-EZH1 complex mediates methylation of histone H3. Both EZH1 and EZH2 are thought to function in the maintenance of embryonic stem cell pluripotency and plasticity and recently have been shown to be essential for hair follicle homeostasis and wound repair. Overexpression of EZH2 has been reported as a marker for advanced and metastatic cancers.