Novel discoveries of the genetic basis of pulmonary hypertension have recently inspired a whole new area of research in pulmonary medicine. The finding that germ-line mutations in the BMPR2 locus, encoding a transmembrane receptor of the TGF beta superfamily, are the cause for familial and partly idiopathic pulmonary arterial hypertension has provided new clues for our understanding of this complex, yet highly localized disease. The TGF beta superfamily comprises more than 40 different growth and differentiation factors essential in the control of proliferation and differentiation of most cell types. In this review, we summarize the novel genetic and functional genomic findings to provide an outlook for the understanding of this disease.