A contiguous stretch of DNA chain inside a fractal globule packs into a compact, unknotted structure, making it easy to pack and unpack. . A team of researchers from Harvard University, the Broad Institute of Harvard and the Massachusetts Institute of Technology (MIT), the University of Massachusetts Medical School, and MIT deciphered the 3-D structure of the human genome, paving the way for new insights into genomic function and expanding our understanding of how cellular DNA folds at scales that dwarf the double helix. Credit: X. Robert Bao, Leonid A. Mirny and Maxim Imakaev