library_construction_protocol: Nano-hmC-Seal was performed as described previously in Han et al. Briefly, 100 ng of genomic DNA were fragmented in tagmentation buffer at 55 °C. Fragmented DNA was purified by Zymo DNA Clean and Concentration Kit (Zymo Research). Then, selective 5hmC chemical labeling was performed in glycosylation buffer (50 mM of HEPES buffer, pH 8.0, 25 mM of MgCl2) containing the fragmented DNA, βGT and N3-UDP-Glc, and incubated at 37 °C for 2 h. After DNA purification in double-distilled H2O, DBCO-PEG4-Biotin (Click Chemistry Tools) was added and incubated at 37 °C for 2 h. The biotin-labeled DNA was pulled down by C1 Streptavidin beads (Thermo Fisher Scientific) for 15 min at room temperature. The captured DNA fragments were subjected to PCR amplification using the Nextera DNA Sample Preparation Kit. The resulting amplified product was purified by 1.0× AMPure XP beads. The input library was made by direct PCR from fragmented DNA directly without labeling and pulldown. The libraries were quantified by a Qubit Fluorometer (Life Technologies Invitrogen Qubit 2.0 DNA RNA Protein Fluorometer, Q32866) and sequenced on a NextSeq 500 Platform in accordance with the manufacturer's protocol.