OVERALL COMPONENT – PROJECT SUMMARY/ABSTRACT The NIH-funded Rare and Atypical Diabetes Network (RADIANT) will continue to refine methods to diagnose individuals with atypical diabetes, identify etiologic genomic variants, and establish the underlying pathophysiology of disease in order to bring precision medicine to clinical practice. In so doing, RADIANT will expand and manage a database and biospecimen repository for storage of data and samples from individuals with rare/atypical forms of diabetes for future analyses. RADIANT includes 14 clinical centers: Baylor College of Medicine (BCM), University of Chicago, University of Washington, Seattle Children’s Hospital, University of Colorado, SUNY Downstate Health Sciences University, Indiana University, Columbia University, Massachusetts General Hospital, University of Maryland, University of Michigan, University of North Carolina, Vanderbilt University, and Washington University in St. Louis. The Data Coordinating Center at the University of South Florida is responsible for the coordination and support of the study protocol, data collection and analysis. The RADIANT Central Laboratory at the University of Florida is responsible for all biochemical analyses, autoantibody testing, DNA and RNA extraction. Whole-genome sequencing and interpretation is conducted at the Broad Institute and RNA sequencing at BCM. Plasma metabolomic profiling is performed at Duke University and monocytes are preserved for pluripotent stem cell derivation at BCM. The study is overseen by the University of Utah Institutional Review Board. The genotypic and phenotypic analyses should enhance the identification of cases with atypical diabetes. Whole-genome sequencing could help identify new genetic variants and metabolomics and transcriptomics analysis novel pathogenic mechanisms and biomarkers for atypical forms of the disease. Its ultimate goal is to enable a more precise, etiologically based clinical classification of diabetes.