[Analysis of genetic mutation and modifier genes in pulmonary arterial hypertension]

Mutations of the bone morphogenetic protein receptor II gene (BMPR2) have been reported in patients with pulmonary arterial hypertension (PAH). In hereditary hemorrhagic telangiectasia (HHT) patients with PAH, missense mutations of the activin receptor-like kinase 1 gene (ALK1) located in the serine-threonine kinase domain. Recently, the mutations of ALK1 in the serine-threonine kinase domain were observed in PAH patients. ALK1 mutations play a critical role in PAH without HHT as well as in PAH with HHT. Because only 10-20% carriers with BMPR2 mutations develop PAH, the existence of environmental factors or modifier genes as 5-HTT(serotonin transporter) and ACE (angiotensin converting enzyme) is highly probable.