P672: The evolving genetic landscape of Phelan-McDermid syndrome and implications for diagnostics

Phelan-McDermid Syndrome (PMS) is a neurodevelopmental disorder caused by disruptions to the SHANK3 gene on chromosome 22q13, encoding a scaffolding protein crucial for synaptic function and neuronal development. PMS presents heterogeneously with intellectual disability, speech impairment/absence, problems with social communication, motor impairments and features of autism spectrum disorder (ASD). SHANK3 deficiency is caused by various genetic abnormalities, including large chromosomal deletions and smaller variants within SHANK3 itself.