Chemerin was confirmed to be significantly elevated in the serum of 15 systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) patients compared to levels in 16 SSc patients without PAH in both the discovery and validation cohorts and was highly correlated with pulmonary vascular resistance (PVR) values, and hence, this protein was proposed as a biomarker of hemodynamic severity in SSc-PAH [5]. The gene discussed is RARRES2; the disease is pulmonary arterial hypertension.