Genome sequencing
Total genomic DNA of FCDK and FCSH was extracted from mixed eggs or juveniles, respectively, using a DNeasy Boold & Tissue kit (Qiagen) following the manufacturer’s protocol. The Illumina sequencing of FCSH was performed by Geneworks (Suzhou, China) using the Illumina HiSeq X platform. The Pacbio sequencing of FCSH and both the Illumina and PacBio sequencing of FCDK were performed by Macrogen (Korea) using the Illumina HiSeq X and PacBio Sequence RSII (P6C4 chemicals) platforms, respectively. The Hi-C experiments were performed by Frasergen (Wuhan, China) following the standard procedure using the Illumina HiSeq X platform. The detailed statistics of all sequencing data are shown in Table 1.