AUTHOR CONTRIBUTIONS
X. W. Gao, P. Liang and B. Zhu planned and coordinated the project. R. Wei and B. Zhu prepared the samples for PacBio and Hi-C. W. J. Hua and B. Zhu prepared the samples for Illumina sequencing. W. L. Zhnag and B. Zhu performed the experiments and analyzed the data. B. Zhu wrote the manuscript. P. Liang revised the manuscript, and all authors approved the final manuscript.