With the advancement of molecular pathogenesis, germline mutations in pheochromocytoma and/or paraganglioma (PPGL) susceptibility genes, such as NF1, RET, VHL, SDHD, SDHC, SDHB, SDHAF2, SDHA, TMEM127, MAX, EPAS1, and FH, have been identified during the past 15 years. Here, RET is linked to hereditary pheochromocytoma-paraganglioma.