“Human development and the human genome have been very well studied,” said Fraser. “My lab is very interested in human evolution, but, because we can build on such a wealth of knowledge, this work can also reveal new insights into the process of evolution more broadly.”

Looking forward, the Fraser lab is working on differentiating the fused cells into other cell types, such as muscle cells, other types of neurons, skin cells and cartilage to expand their studies of uniquely human traits. The Pașca lab, meanwhile, is interested in investigating genetic dissimilarities related to astrocytes – large, multi-functional cells in the central nervous system often overlooked by scientists in favor of the flashier neurons.

“While people often think about how neurons have evolved, we should not underestimate how astrocytes have changed during evolution. The size difference alone, between human astrocytes and astrocytes in other primates, is massive,” said Pașca. “My mentor, the late Ben Barres, called astrocytes ‘the basis of humanity’ and we absolutely think he was onto something.”

Additional Stanford co-authors for the Nature paper are former research assistant Danqiong Sun, postdoctoral scholar Fikri Birey, senior research scientist Se-Jin Yoon, postdoctoral scholar Yuki Miura and former research associate Karen Sabatini.

This work was funded by a Stanford Bio-X Interdisciplinary Initiatives Seed Grant, the National Institutes of Health, the Department of Defense, the Stanford Center for Computational, Evolutionary and Human Genomics, the Stanford Medicine’s Dean’s Fellowship, MCHRI, the American Epilepsy Society, the Stanford Wu Tsai Neurosciences Institute’s Big Idea Grants on Brain Rejuvenation and Human Brain Organogenesis, the Kwan Research Fund, the New York Stem Cell Robertson Investigator Award, and the Chan Zuckerberg Ben Barres Investigator Award.

Additional Stanford co-authors for the Nature Genetics paper are graduate student Maia Kinnebrew; former undergraduate Wei Gordon; former technician Danqiong Sun; postdoctoral research fellows Vivek Bajpai and Sahin Naqvi; Dmitri Petrov, the Michelle and Kevin Douglas Professor in the School of Humanities and Sciences; Joanna Wysocka, the Lorry Lokey Professor and professor of developmental biology; and Rajat Rohatgi, associate professor of biochemistry and of medicine. Researchers from University of California, San Francisco; University of Michigan, Ann Arbor; Yerkes National Primate Research Center; Emory University School of Medicine; and University of Pennsylvania are also co-authors.

This work was funded by the Human Frontier, Rothschild and Zuckerman fellowships, and the National Institutes of Health.

Fraser is a member of Stanford Bio-X, the Maternal & Child Health Research Institute (MCHRI), and the Stanford Cancer Institute. Pașca is a member of Stanford Bio-X, MCHRI and the Wu Tsai Neurosciences Institute, and a faculty fellow of Stanford ChEM-H.

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Media Contacts

Taylor Kubota, Stanford News Service: (650) 724-7707; tkubota@stanford.edu