Identification of multiple ACVRL1 mutations in patients with pulmonary arterial hypertension by targeted exome capture.
Pulmonary artery hypertension (PAH) is characterized as sustained elevation of pressure in the pulmonary vascular system that is attributable to a variety of causes. More than a dozen genes have previously been proposed as being associated with PAH. To examine potential mutations of these genes in patients with PAH, we developed a targeted exome kit containing 22 PAH-associated genes for genetic screens of 80 unrelated patients with PAH. As a result, we identified 16 different mutations in the BMPR2 gene and four different mutations in ACVRL1, the gene for activin receptor-like kinase-1 (ACVRL1). However, no deleterious mutations were found in the remaining 20 genes. In the present study, we provided detailed characterization of the ACVRL1 mutations in four pedigrees, including two novel missense mutations (c.676G>A, p.V226M; c.955G>C, p.G319R) and two recurrent mutations (c.1231C>T, p.R411W; c.1450C>T, p.R484W). Furthermore, we showed that markedly reduced Smad1/5 phosphorylation levels and reduced activities of luciferase reporters in each of the four ACVRL1 mutant-transfected NIH-3T3 cells. Therefore, our findings demonstrated that missense mutations of ACVRL1 identified in the present study significantly affected the bone morphogenetic protein 9 (BMP-9) pathway, implicating PAH pathogenesis. Detailed genotype-phenotype correlation analysis revealed initial symptoms of hereditary haemorrhagic telangiectasia (HHT) in some of the patients, suggesting the importance of sequencing molecular markers for early identification and intervention of individuals at risk for PAH and potential HHT. We developed a customized exome sequencing system to identify mutations in these PAH-associated genes, and found two novel missense mutations and two recurrent mutations in the ACVRL1 gene in four unrelated Chinese families; we also determined hypomorphic alleles using functional studies.
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Chunmei
C
Piao
Department of Paediatric Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
Yan
Y
Zhu
Department of Paediatric Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
Chen
C
Zhang
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Xin
X
Xi
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Xuxia
X
Liu
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Shuai
S
Zheng
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Xiaoyan
X
Li
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Jun
J
Guo
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Lixin
L
Jia
Department of Paediatric Cardiology, the Heart Institute, Tokyo Women's Medical University, Tokyo, Japan.
Toshio
T
Nakanishi
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China.
Tao
T
Cai
Department of Paediatric Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China koko_gu@hotmail.com jdu@bcm.edu.
Hong
H
Gu
Beijing Anzhen Hospital, Capital Medical University, Beijing, China Beijing Collaborative Innovation Centre for Cardiovascular Disorders, Beijing, China The Key Laboratory of Remodelling-Related Cardiovascular Diseases, Ministry of Education, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing 100029, China koko_gu@hotmail.com jdu@bcm.edu.
Jie
J
Du
D030301:Activin Receptors, Type II / Q000235:genetics* / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000818:Animals; D002648:Child; D059472:Exome; D005260:Female; D055427:Growth Differentiation Factor 2 / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006976:Hypertension, Pulmonary / Q000235:genetics* / Q000378:metabolism; D008297:Male; D051379:Mice; D009154:Mutation; D041681:NIH 3T3 Cells; D010375:Pedigree; D015398:Signal Transduction; D055815:Young Adult
D055427:Growth Differentiation Factor 2; C425364:ACVRL1 protein, human; D030301:Activin Receptors, Type II
ACVRL1; Chinese; HHT; PAH; target-captured exome sequencing