PHOX2B and Strabismus: Symptoms due to autonomic nervous system dysfunction/dysregulation (ANSD)—including strabismus (27%), dysphagia (27%), abnormal heart rhythm (10%), breath-holding spells (9%), and recurrent seizures due to hypoglycemia (9%)—were associated with an increased number of polyalanine repetitions of exon 3 or NPARMs of PHOX2B gene.