Neuron-specific chromatin signatures in human prefrontal cortex. Bar graphs showing ChIP-to-input ratio (y-axis) for trimethylated H3-lysine 4 (H3K4me3) at GRIN2B, BDNF and B2M promoters, and HBB (β-globin) locus control region in chromatin of NeuN positive (NeuN+) and negative (NeuN-) FACS sorted nuclei from human prefrontal cortex. Data shown as mean ± S.E.M., N = 3 specimens/sorting. The NeuN+ fraction showed, in comparison to NeuN- fraction of the same subject, increased levels of H3K4me3 at GRIN2B and BDNF in 3/3 cases. Notice further the extremely low ChIP-to-input ratio for HBB.