A very recent unbiased whole-blood transcriptome analysis in PAH patients and healthy controls (HCs) [20] identified a signature of 507 PAH-associated genes, in which T cell signaling, phosphoinositide 3-kinase (PI3K) signaling in B lymphocytes and interleukin-6 (IL-6) signaling were among the top canonical pathways. This evidence concerns the gene IL6 and pulmonary arterial hypertension.