Table 1. Transcriptional signature characteristics of hereditary PPGL.

Transcriptional signature
Cluster 1 group (10-15%)	Cluster 2 group (50-60%)	Cluster 3 group (5-10%)
Cellular response to hypoxia	Proteins that activate kinase signaling	Via Wnt
Extra-adrenal syndrome + von Hippel-Lindau	Adrenal	Adrenal + Extra-adrenal
Germline / Somatic	Germline / Somatic	Somatic
Normetanephrine / 3-Methoxytyramine (3-MT)	Normetanephrine + metanephrine or metanephrine only	Normetanephrine metanephrine / Chromogranin A
SDHD, SDHC, SDHB, SDHA, SDHA2F, VHL, HIF, FH, EGLN1 (PHD2), EGLN2 (PHD1), KIF 1β, EPAS1/2 (HIF2A), MDH2	RET, NF1, MAX, TMEM127, HRAS	CSDE1, MAML3