The observed abnormal phenotypes in DA neuronal culture using PTPS deficiency iPSCs are consistent with the symptoms of motor disturbance and reduced homovanillic acid (HVA), one of the catecholamine metabolites in cerebrospinal fluid (CSF), which are found in patients with PTPS deficiency. The gene discussed is PTS; the disease is hyperinsulinemic hypoglycemia, familial, 4.