SDHD and von Hippel-Lindau disease: Classic PPGL-related genetic syndromes include multiple endocrine neoplasia type 2 (MEN 2), von Hippel–Lindau syndrome, neurofibromatosis 1, and PGL1-5, which are caused by pathogenic germline mutations in RET, VHL, NF1, SDHD, SDHAF2, SDHC, SDHB, and SDHA genes, respectively.