ChIP were produced from E13.5 metanephros. Pairs of metanephros were individually fixed in 1% Formaldehyde for 20 minutes at room temperature and stored at -80°C. Genotyping was done on tail biopsies. Shearing was performed on a Bioruptor (Diagenod) in 1% SDS. ChIP was done by over-night incubation of protA/protG magnetic beads conjugated with the desired antibody in 1.2ml dilution buffer, rotating at 30 rpm 4°C. Washes were performed in 1ml of washing buffers, incubated at 4°C for 2 minutes: 2x RIPA/2x RIPA-500mM NaCl/2x LiCl/2x TE. Beads were eluted and chromatin fixation was reversed during an over-night incubation at 65°C in presence of proteinase K. The eluate was treated with RNase A, PCI purified and precipitated. 5-10 ng of purified DNA were used to built libraries according to the manufacturer's protocol (Illumina). The material was sequenced with 100 bp single-end reads on the Illumina HiSeq according to the manufacturer's specifications.