Clinicians should consider CACNA1D as high-risk gene for newborns with a prominent jittering phenotype and immediately screen the child for additional symptoms associated with CACNA1D mutations, in particular those of acute relevance such as high risk for hyperinsulinemic hypoglycemia and hypertension due to primary aldosteronism (22). Here, CACNA1D is linked to hyperinsulinemic hypoglycemia.