Lymphocytes were harvested as described in manuscript. Fresh cells were prepared as previously described (Buenrostro et al., 2013). Briefly, cells were washed in cold PBS and lysed. Transposition occurred at 42°C for 45 minutes. DNA was purified using the MinElute PCR purification kit (Qiagen) and amplified for 5 cycles. Additional PCR cycles were evaluated by real time PCR. Final product was cleaned by Ampure Beads at a 1.5x ratio. Libraries were sequenced on a Hiseq 2500 1T in a 50bp/50bp paired-end run, using the TruSeq SBS Kit v3 (Illumina). An average of 51 million paired reads were generated per sample.