An autosomal dominant neurodevelopmental condition related to variants in CACNA1D. Most reported variants are de novo and functional studies have indicated a gain-of-function disease mechanism. This condition is characterized by developmental delay/intellectual disability, autism spectrum disorder, hypotonia and seizures. Other reported features include endocrine abnormalities such as primary aldosteronism and congenital hyperinsulinemic hypoglycemia, self-injurious behavior, facial dysmorphisms, and heart defects.