After disruption with a Dounce homogenizer lysates were sonicated and the DNA sheared to an average length of 300-500 bp. Chromatin (30 ug) was precleared with protein A agarose beads. Incubated with 20 ul antibody against Lmx1b (BMO8)53 kindly provided Dr. Witzgall.. Crosslink was reversed Proteinase K digestion and incubation overnight at 65 °C. ChIP DNA was purified by phenol-chloroform extraction and ethanol precipitation. After end-polishing, dA-addition, adaptor ligation and final PCR amplification step, the resulting DNA libraries were quantified and sequenced on Illumina’s NextSeq 500.