Today in @Nature, we report a new approach to studying human brain development and modeling disease in vivo. Human neural #assembloids# and #organoids# have opened new ways to study development in vitro, but they also have important limitations. Transplantation can provide a more physiological environment, yet human cortical cells then develop within a rodent brain that matures much faster, constraining their growth and integration. To address some of these limitations and obtain more advanced functional readouts relevant to disease biology, we generated #apallial# mice, in which ~98% of the cortex and hippocampus fail to form, creating space for transplanted human cortical organoids to grow and integrate extensively. We call these #xenocortical# mice (XCX). Nearly 7 years in the making. Congratulations to an extraordinary team and wonderful collaborators! Link to the article below 👇