Somatic Mosaicism in Human Development, Aging, and Diseases - ABSTRACT Support is requested for a Keystone Symposia conference entitled Somatic Mosaicism in Human Development, Aging, and Diseases, organized by Drs. Jeong Ho Lee, E. Alice Lee and Peter Campbell, with scientific programming input from Keystone Symposia. The meeting will take place February 17–20, 2025 at the Beaver Run Conference Center in Breckenridge, Colorado USA. The study of somatic mosaicism is beginning to reframe our understanding of human genetics, development, aging and the important links between genes and diseases. Comprehensive analysis of the genetic variation that defines somatic mosaicism allows us to trace lineage evolution from the fertilized egg to human embryo to adult organs, along with defining developmental and aging processes at single-cell resolution. It is recognized that this field of study is at an early stage and requires advanced experimental and computational genomic technologies, which is of particular relevance to the mission of the National Human Genome Research Institute (NHGRI). This Keystone Symposia conference represents one of the first focused events on somatic mosaicism designed to convene an interdisciplinary research community around this field and to bring together scientists and clinicians from developmental and aging biology, bioinformatics, systems biology, genetics and genomics, who will collaboratively explore the intersection of these diverse fields. The conference will also attract participation from researchers in industry, who recognize the nascent translational opportunities in somatic mosaicism research. The program will integrate diverse aspects of somatic mosaicism, connecting with genomics innovations, mechanistic analyses and translational opportunities, all of which fall within the remit of NHGRI.