IFNB1 and pulmonary arterial hypertension: Although in many cases of IFN-α related PAH there are other risk factors for development of PAH, and IFN treatment seems to be a “trigger”, but as mentioned, there are some “pure” cases of PAH after IFN-β therapy, and IFN is now considered as a “possible” risk factor for PAH.3 As PAH is a serious condition, it seems reasonable to conduct well designed, clinical and experimental research to better understand the underlying mechanism of IFN-related PAH.