HOXA9 and leukemia: ChIP–seq profiling of Stat5a, Runx1 and Runx2 confirmed the motif analysis, demonstrating cobinding of these transcription factors and BAF or MLL1 and MLL4 complexes at key pro-leukemia genes including Hoxa7 and Hoxa9 (Fig. 6c,d and Extended Data Fig. 10e).