(RESEARCH PLAN- OVERALL) PROJECT SUMMARY With this application, we seek funding for the Intellectual and Developmental Disabilities Research Center (IDDRC) at the Children’s Hospital of Philadelphia (CHOP) and the University of Pennsylvania (Penn), which has been continuously funded for the past 30 years. Our IDDRC supports an interdisciplinary program and is the chief agency at CHOP/Penn for the promulgation of research into the Intellectual and Developmental Disabilities (IDDs). Our mission, to identify the pathogenesis of and develop therapies for individuals with IDDs, is pursued through three aims. (Aim 1) Lead a cutting-edge IDD research agenda. We will support five research cores that harness innovations in genetics and neuroscience to identify the causes of IDDs, to determine how gene variants alter brain structure, circuitry, and behavioral outputs (cognitive, motor, sensory, social, affective), and to utilize this information to develop biomarkers and new treatments for IDDs. Our cores deploy complementary state-of- the-art technologies, focusing on studies performed in two species (mouse & human), making it easier for center members to perform more impactful research. Cores emphasize research along the developmental spectrum. These strategies ensure that the advances will have a translational impact. The cores provide cost-effective support for 61 world-class center members, who are funded by 78 grants totaling $29.1 million annually to study the pathogenesis of IDDs, to identify new biomarkers of IDDs, and to develop novel interventions (pharmacologic and genetic). In addition, we will support an innovative research project that uses center cores to determine if magnetoencephalography (MEG) measures of auditory processing in infants at genetic risk for IDD can be used to predict cognitive and language outcome. Our cores focus on rigorous and reproducible research practices, including sound experimental design for hypothesis testing, well-justified sample sizes, and robust data analytics. (Aim 2) Lead a multi-disciplinary career development program to support trainees and early-stage faculty. Our trainees are diverse and have PhDs, MDs, and MD/PhDs with backgrounds in genetics, neuroscience, and related disciplines. They receive support from IDDRC-administered programs: a NINDS-funded T32 Training Grant in Neurodevelopmental Disabilities, a CHOP Research institute-funded supplement program for clinical research fellows, and a CHOP-institute funded New Program Development award for Assistant Professors. They obtain multidisciplinary training that helps them become future leaders in IDD research. (Aim 3) Support Networking/Collaboration, Advocacy, and the Dissemination of IDD Research findings. The Center leadership will enable networking to support collaborative initiatives, both within the CHOP/Penn IDDRC community and between IDDRCs. Center leadership will advocate both internally and externally to advance an IDD research agenda. Fina...