Kim Nasmyth

Kim Nasmyth elucidated the molecular structure and function of the cohesin complex as a ring-shaped ATPase that entraps DNA, discoveries fundamental to understanding both sister chromatid cohesion and 3D genome organization through loop extrusion. His loop extrusion model, in which cohesin actively extrudes chromatin loops until blocked by CTCF boundary elements, has become the dominant mechanistic framework for TAD formation. His work has illuminated how cohesin mutations found in myeloid malignancies, bladder cancer, and Ewing sarcoma disrupt chromatin loop architecture to cause gene dysregulation. His contributions to chromatin biology earned him the Breakthrough Prize in Life Sciences.