Fig. 2

A brief overview of sequencing techniques. Chromosome conformation capture technologies: a Chromosome spatial organization analysis in 3C technology starts with cell population crosslinking and fragmentation with a restriction enzyme. Next, it goes through intramolecular ligation and reverse-crosslinking and performs semi-quantitative or quantitative PCR. b Chromosome spatial organization analysis in 4C technology starts with cell population crosslinking and fragmentation with restriction enzyme. Next, it goes through intramolecular ligation and reverse crosslinking. Next, it goes through digestion with a restriction enzyme and ligation, and finally, applies inverse PCR. c Chromosome spatial organization analysis in 5C technology starts with cell population crosslinking and fragmentation with a restriction enzyme. Next, it goes through intramolecular ligation and reverse-crosslinking and performs synthetic ligation and multiplex PCR. d Chromosome spatial organization analysis in ChIA-PET technology starts with cell population crosslinking and fragmentation with a restriction enzyme. Then, DNA linker ligation attracts nucleotides and performs reverse crosslinking and PCR. e Chromosome spatial organization analysis in Hi-C technology starts with cell population crosslinking and fragmentation with restriction enzyme. Then, it attaches biotin-labeled nucleotide, and goes through blunt ligation and PCR [1, 2, 10, 13, 17, 66, 67]. f First, HiC-TrAC creates a bridge on chromatin loops and splices DNA with restriction enzymes. Then, the process is fertilized with streptavidin beads. Finally, DNA fragments having a biotin label attach with a multiplexing adapter and go through a PCR amplification [9]