Genetic causes of pulmonary arterial hypertension (PAH) and pulmonary veno-occlusive disease (PVOD) have been identified, leading to a growing need for genetic counselling.Between 2003 and 2014, genetic counselling was offered to 529 PAH and 100 PVOD patients at the French Referral Centre for Pulmonary Hypertension.Mutations in PAH-predisposing genes were identified in 72 patients presenting as sporadic PAH (17% of cases; 62 mutations in BMPR2, nine in ACVRL1 (ALK1) and one in ENG) and in 94 patients with a PAH family history (89% of cases; 89 mutations in BMPR2, three in ACVRL1 (ALK1) and two in KCNK3).
Four bone morphogenetic protein receptor II (BMPR2) mutations have been previously described in PVOD patients; in the current study we describe 2 additional cases of BMPR2 mutation in PVOD.
GCN2 expression was abolished in heritable PVOD (p < 0.0001), but also importantly decreased in sporadic PVOD (p = 0.03) as well as in heritable (p = 0.002) and idiopathic PAH (p = 0.003); moreover, GCN2 was abolished in 2 experimental pulmonary hypertension models and importantly decreased in 1 model (p < 0.0001 for all models).
Notably, EIF2AK4 gene was also involved in the panel, which allowed to distinguish pulmonary veno-occlusive disease (PVOD)/pulmonary capillary hemangiomatosis (PCH) patients from idiopathic PAH (IPAH).
The aims of this study were phenotypical characterization and survival analysis of Iberian Romani patients with familial PVOD carrying the founder p.Pro1115Leu mutation in EIF2AK4, according to their tolerance to pulmonary vasodilators (PVD).
Mutations in eukaryotic translation initiation factor 2 alpha kinase 4 (EIF2AK4) cause heritable PVOD and PCH, whereas mutations in other genes cause HPAH.
The recent discovery of biallelic mutations in the EIF2AK4 gene as the cause of heritable PVOD/PCH represents a major milestone in our understanding of the molecular pathogenesis of PVOD.
Bi-allelic mutations in EIF2AK4 were identified in all patients with a family history of PVOD (n=19) and in seven patients (8.6%) presenting as sporadic PVOD.
Absence of significant trichloroethylene exposure was associated with a younger age of disease (54.8±21.4 years, p=0.037) and a high prevalence of harbouring bi-allelic EIF2AK4 mutations (41.7% versus 0%, p=0.015).Occupational exposure to organic solvents may represent a novel risk factor for PVOD.
These findings point to EIF2AK4 as the major gene that is linked to PVOD development and contribute toward an understanding of the complex genetic architecture of pulmonary hypertension.
Our study is the first to show remarkable histological structures, including the wreath-like arrangement of a hyperplastic muscle bundle in the adventitia of pulmonary arteries, in PVOD patients as a diagnostic clue and to disclose the biological difference between PAH and PVOD in a Taiwanese population.
In a recent article published in the journal, Yang and his colleagues found pulmonary edema was not demonstrated in 2 of the 6 PVOD patients injected with prostacyclin analogues (a kind of PAH-targeted drug).
The three patients with PVOD had a very severe disease at diagnosis and required a lung transplantation.The genetic architecture of paediatric PAH is enriched in ACVRL1 and TBX4 mutations compared to adult PAH, but further studies are required to confirm these results.
The three patients with PVOD had a very severe disease at diagnosis and required a lung transplantation.The genetic architecture of paediatric PAH is enriched in ACVRL1 and TBX4 mutations compared to adult PAH, but further studies are required to confirm these results.
Genetic causes of pulmonary arterial hypertension (PAH) and pulmonary veno-occlusive disease (PVOD) have been identified, leading to a growing need for genetic counselling.Between 2003 and 2014, genetic counselling was offered to 529 PAH and 100 PVOD patients at the French Referral Centre for Pulmonary Hypertension.Mutations in PAH-predisposing genes were identified in 72 patients presenting as sporadic PAH (17% of cases; 62 mutations in BMPR2, nine in ACVRL1 (ALK1) and one in ENG) and in 94 patients with a PAH family history (89% of cases; 89 mutations in BMPR2, three in ACVRL1 (ALK1) and two in KCNK3).
Genetic causes of pulmonary arterial hypertension (PAH) and pulmonary veno-occlusive disease (PVOD) have been identified, leading to a growing need for genetic counselling.Between 2003 and 2014, genetic counselling was offered to 529 PAH and 100 PVOD patients at the French Referral Centre for Pulmonary Hypertension.Mutations in PAH-predisposing genes were identified in 72 patients presenting as sporadic PAH (17% of cases; 62 mutations in BMPR2, nine in ACVRL1 (ALK1) and one in ENG) and in 94 patients with a PAH family history (89% of cases; 89 mutations in BMPR2, three in ACVRL1 (ALK1) and two in KCNK3).
The objective of this study was to determine the mutation frequency in PH genes in a paediatric cohort and describe the clinical characteristics of mutation carriers.The study involved 66 index cases with PH: 35 children with idiopathic pulmonary arterial hypertension (IPAH); five children with familial PAH (FPAH); three children with pulmonary veno-occlusive disease (PVOD); and 23 children with PAH associated with congenital heart disease (APAH-CHD).No mutations were found in the 23 children with APAH-CHD.
The three patients with PVOD had a very severe disease at diagnosis and required a lung transplantation.The genetic architecture of paediatric PAH is enriched in ACVRL1 and TBX4 mutations compared to adult PAH, but further studies are required to confirm these results.