To identify other potential transcription factors that directly regulate the expression of FTO, we analyzed ENCODE ChIP-seq datasets using ChIPBase [33] and found that the hematopoietic transcription factor PU.1 (encoded by SPI1 gene) bound directly to the FTO promoter within 1 kb upstream of the transcription start site (TSS) in the HL-60 cells, an acute promyelocytic leukemia cell line. The gene discussed is SPI1; the disease is acute promyelocytic leukemia.