2025 ACMG ANNUAL CLINICAL GENETICS MEETING POSTER PRESENTATION

Clinical Utility and Diagnostic Yield of Comprehensive Genetic Testing in Adults with Intellectual and Developmental Disabilities (IDD): A Single-Center Experience 

Genetic testing is a standard of care for children with intellectual and developmental disabilities (IDD) but remains underutilized in adult populations despite significant advancements in genomic technologies such as whole exome sequencing (WES), whole genome sequencing (WGS), and chromosomal microarray analysis (CMA). This study evaluates the diagnostic yield and clinical utility of these testing modalities in adults with IDD, addressing existing disparities in care and access. A retrospective analysis of 69 adults referred to SequenceMD between 2022 and 2024 demonstrated an overall diagnostic yield of 37.7%, with WES/WGS outperforming gene panels (73.1% vs. 23.1%). Clinical utility outcomes included therapeutic interventions (27.5%), preventive care (34.8%), and long-term planning (37.7%), emphasizing the value of genomic testing in optimizing adult IDD management. These findings advocate for updating clinical guidelines to include WES/WGS as foundational diagnostic tools for adults with IDD.