design: For the Nanopore sequencing, DNA was end-polished and A-tailed (NEBnext ultra II end repair kit, New England Biolabs, MA, USA). The end-prepared samples were barcoded using Blunt/TA ligase master mix (M0367L). The library was prepared by ligating sequencing adapters (SQK-NBD114.24) onto double-stranded DNA fragments using NEB Quick T4 DNA Ligase (New England Biolabs, MA, USA). After purification with AMPure XP beads, the prepared library was ready for sequencing.