Highly purified double-positive ERMS cells engrafted robustly and made ERMS tumors that contained all fluorescent tumor cell subfractions, including the less differentiated myf5-GFP+/mylz2-mCherry-negative ERMS cells (n = 3 of 3; Figures S2Q– S2V; Table S3). Here, MYF5 is linked to neoplasm.