Known pathogenic variation in SDHB/RET, BRCA1/2, and MMR genes is thought to be responsible for a subset of pheochromocytoma and paraganglioma, breast, ovarian, colon, and uterine cancers in TCGA [9, 10, 43, 48]. This evidence concerns the gene MRC1 and hereditary pheochromocytoma-paraganglioma.