Down Syndrome: Genetic Basis, Clinical Features, and Lifespan Health Management

Down syndrome (trisomy 21) is the most common viable autosomal trisomy and leading genetic cause of intellectual disability, characterized by distinctive physical features and neurodevelopmental differences with variable multi-system involvement. Individuals with Down syndrome face heightened lifelong health risks including congenital heart disease, hematologic and autoimmune disorders, sleep-disordered breathing, and early-onset Alzheimer disease, requiring coordinated interprofessional care and early detection of comorbidities.