Severe pulmonary hypertension after the discovery of the familial primary pulmonary hypertension gene

The recent discoveries of the familial primary pulmonary hypertension gene and somatic mutations in key cell growth and cell death regulatory genes in primary pulmonary hypertension have added a new dimension to severe pulmonary hypertension research. These findings have already impacted on how the disease is viewed, and ultimately, how severe pulmonary hypertension is diagnosed and treated. However, this new information raises several fundamental questions related to the role of bone morphogenetic protein receptor signalling in the control of lung vascular cell function. Furthermore, additional genes and gene products may also be involved in the pathogenesis of the disease. The way severe pulmonary hypertension is viewed and studied is on the verge of shifting from a vasoconstrictive to a cell growth paradigm.