Inflammation may impact further on dysfunctional BMPR2 signaling and loss of iron homeostasis, as plasma IL-6 levels are raised in patients with PAH (Selimovic et al., 2009); IL-6 is also known to up-regulate hepcidin expression via the JAK-STAT pathway (Soon et al., 2010) (Figure 2). The gene discussed is BMPR2; the disease is pulmonary arterial hypertension.