The study investigates the three-dimensional organization of mitotic chromosomes using chromosome conformation capture methods (5C and Hi-C) across the cell cycle. The researchers found two distinct folding states: a compartmentalized and cell-type-specific state in interphase, and a homogenous, locus-independent state in metaphase. In metaphase, chromosomes exhibit a linearly organized, longitudinally compressed array of consecutive chromatin loops, which is consistent across different cell types. Polymer simulations support this model, suggesting that metaphase chromosome organization results from a two-stage process: linear compaction by consecutive chromatin loops and axial compression. This work provides new insights into the structural and organizational principles of mitotic chromosomes.The study investigates the three-dimensional organization of mitotic chromosomes using chromosome conformation capture methods (5C and Hi-C) across the cell cycle. The researchers found two distinct folding states: a compartmentalized and cell-type-specific state in interphase, and a homogenous, locus-independent state in metaphase. In metaphase, chromosomes exhibit a linearly organized, longitudinally compressed array of consecutive chromatin loops, which is consistent across different cell types. Polymer simulations support this model, suggesting that metaphase chromosome organization results from a two-stage process: linear compaction by consecutive chromatin loops and axial compression. This work provides new insights into the structural and organizational principles of mitotic chromosomes.