All had normal levels for Chromogranin A (0–85 ng/mL), a tumor marker for pheochromocytomas/paragangliomas, except for patients No. 7 (156.5 ng/mL), 26 (231.4 ng/mL) and 27 (224.7 ng/mL). The gene discussed is CHGA; the disease is hereditary pheochromocytoma-paraganglioma.