design: The high molecular weight DNA sample was fragmented to obtain double-stranded DNA fragments with appropriate size. The genomic DNA sample was checked on Genomic DNA ScreenTape after fragment. Then DNA fragments were end-polished and A-tailed.The end-prepared samples were barcoded using Blunt TA ligase master mix. The equimolar concentration of barcoded sample was pooled and library was prepared by ligating sequencing adapters onto double-stranded DNA fragments using NEB Quick T4 DNA Ligase. After purification with AMPure XP beads, the prepared library was ready for library quality control.