design: Genomic DNA was sheared to an average size distribution of 10 kb using g-TUBEs (Covaris, Woburn, USA) and subsequently purified. Purified DNA fragments were added to the enzyme reaction tubes and incubated at 37C for 15 minutes to remove single-strand overhangs followed by the addition of repair mix and incubation at 37C for 30 minutes to repair the damage within the DNA backbone. After DNA damage repair, the ends of the double-stranded fragments were polished and subsequently tailed with an A-overhang by adding End Prep Mix and incubating at 20C for 10 minutes and then at 65C for 30 minutes. Ligation with T-overhang SMRTbell adapters occurred at 20C for 60 minutes, after which the AMPure PB beads (Pacific Biosciences, Menlo Park, USA) were employed to purify the SMRTbell library. Due to the presence of short fragments after the first purification step, the library was size-selected with AMPure PB beads (Pacific Biosciences) to remove SMRTbell fragments less than 3 kb. Subsequently, the size distribution and quantity of the SMRTbell library to be sequenced were measured using Invitrogen Qubit 3.0 Fluorometer (Thermo Fisher Scientific) and Agilent 2100 Bioanalyzer (Agilent Technologies, Santa Clara, USA).