The binding motif for PU.1 (a transcription factor critical for myeloid and B-lymphoid cell development and function and an AD risk gene (SPI1)12) was the best match for the most highly overrepresented sequence motif in active enhancers across all three cell types, followed by AP-1, C/EBP, CTCF, and RUNX binding motifs. Here, CTCF is linked to Alzheimer disease.