library_construction_protocol: Qiagen DNeasy Blood & Tissue Kit 500 ng of genomic DNA was spiked with 0.5% (w/w) of unmethylated lambda phage DNA (Promega) for calculation of the bisulfite non-conversion rate, and sheared with a Covaris S2 sonicator to an average length of 300 bp. The sheared DNA was end-repaired, A-tailed and ligated to methylated adapters (NEXTflex Bisulfite-Seq Barcodes, PerkinElmer) using the NxSeq AmpFREE Low DNA Library Kit (Lucigen). Adapter ligated libraries were subject bisulfite conversion using the EZ DNA Methylation-Direct Kit (Zymo) following the manufacturer's instructions and subjected to 6 cycles of PCR amplification using KAPA HiFi Uracil+ DNA polymerase (KAPA Biosystems).