title: Genetic aspects of pulmonary arterial hypertension.
abstract: This paper concentrates on the genetic aspects of pulmonary arterial hypertension (PAH), a diagnostically based subclass of pulmonary hypertension that includes primary pulmonary hypertension (PPH). During the past year, patients with familial and sporadic PPH were found to have germline heterozygous missense, nonsense and frameshift mutations in bone morphogenetic protein receptor II (BMPR2). Mutations in BMPR2, a member of the transforming growth factor-beta (TGF-beta) receptor superfamily, are predicted to interrupt the bone morphogenetic protein (BMP) signalling pathway, resulting in proliferation, rather than apoptosis of cells within small arterioles. Mechanistically, haploinsufficiency was found by using in vitro gene expression experiments, but a dominant-negative mechanism has not been excluded. The failure to find BMPR2 mutations in all families with familial PPH and in all patients with sporadic PPH suggests that other genes remain to be identified. Mutations in ALK1, a TGF-beta type 1 receptor, previously known to cause type 2 hereditary haemorrhagic telangiectasia (HHT), have also been reported in a few HHT families with clinical and histological features of PPH. The clinical development of PPH, as in neoplasia, appears to require 'two hits' The two hits can be provided either by genetic or environmental factors.
authors.affiliation: Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA. jhm4@columbia.edu
authors.forename: J H
authors.initials: JH
authors.lastname: Morse
authors.forename: Z
authors.initials: Z
authors.lastname: Deng
authors.forename: J A
authors.initials: JA
authors.lastname: Knowles
mesh_terms: D000818:Animals; D052006:Bone Morphogenetic Protein Receptors, Type II; D016368:Frameshift Mutation; D006801:Humans; D006976:Hypertension, Pulmonary / Q000235:genetics*; D020125:Mutation, Missense; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D013683:Telangiectasia, Hereditary Hemorrhagic; D016212:Transforming Growth Factor beta / Q000502:physiology
chemical_list: D011956:Receptors, Cell Surface; D016212:Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; C498218:BMPR2 protein, human; D052006:Bone Morphogenetic Protein Receptors, Type II