PDE2A and Chorea: In conclusion, results from our genetic and functional studies indicate a PDE2A p.Asp480Gly homozygous loss‐of‐function mutation as the likely genetic cause of early‐onset hereditary chorea in our family, thus possibly expanding the genetic aetiology of early‐onset choreic/hyperkinetic movement disorders associated to abnormal c‐AMP and c‐GMP metabolism in striatal MSNs.