(N) inset, top, schematic diagram of the BRCA1 promoter and relative positions of primer sets used in this study. ChIP analysis at the BRCA1 promoter using KLF4-specific or nonspecific control IgG (α-Gal4) in MDA-MB-231 cells. Shown is the enrichment at positions of the BRCA1 locus relative to the TSS, presented as percent recovery of input. 