library_construction_protocol: Genomic DNA, total RNA were extracted from approximately 10 mg of proximal colon tissue using AllPrep DNA/RNA mini kit (QIAGEN, Hilden, Germany). RRBS and oxRRBS libraries were prepared by Ovation® RRBS Methyl-Seq with TrueMethyl® oxBS kit (Tecan, Redwood City, CA) according to the manufacturer's instructions.