Germline mutations in at least 25 different genes have been reported to predispose to PC/PGL/HNPGL or RCC (NF1, RET, MAX, EGLN1, EGLN2, MSH2, KIFIB, SDHAF2,MEN1, BAP1, CDC73, CDKN2B, FLCN, MET, PBRM1, PTEN, TSC1, TSC2, FH, SDHA, SDHB, SDHC, SDHD, TMEM127, and VHL) (6–9, 12–14, 15). The gene discussed is TSC1; the disease is pachyonychia congenita.