Malformations & Mosaicism: Role of Oncogenic Variants & Genetic Complexity in Developmental Lesion

Many pediatric malformations, ranging from congenital nevi to vascular malformations and congenital pulmonary airway malformations, arise secondary to mosaic variants that occur in utero. These variants are often the same oncogenic variants which result in malignant lesions in adults. Furthermore, a subset of these mosaic lesions are genetically complex with somatic pathogenic variants in more than one gene, a phenomenon more typically associated with cancer. This lecture will provide an overview on the spectrum of developmental lesions associated with oncogenic variants, differential effects of these variants during development, and emerging data on cancer risks in individuals with these lesions. After viewing this lecture, participants should be able to: 1. Recognize the role of oncogenic variants in vascular malformations and other somatic mosaic lesions. 2. Describe underlying reasons for the phenotypic heterogeneity in mosaic RASopathies. 3. Summarize current data on genetic complexity in vascular anomalies and recognize the multitude of unanswered questions in this area. Nya Nelson, MD, PhD Assistant Professor, Dept. of Laboratory Medicine & Pathology University of Washington Assistant Director, Molecular Diagnostics, Seattle Children’s Hospital Pathologist, Seattle Children’s Hospital 02/09/26 The University of Washington is committed to ensuring digital accessibility in our services, programs, and activities. If you encounter accessibility barriers using videos found on this channel, please contact UW Video at uwvideo [at] uw [dot] edu.