A polymorphism consisting of the presence or absence of a 250-bp DNA fragment was detected within the angiotensin I-converting enzyme gene (ACE) using the endothelial ACE cDNA probe. This polymorphism was used as a marker genotype in a study involving 80 healthy subjects, whose serum ACE levels were concomitantly measured. Allele frequencies were 0.6 for the shorter allele and 0.4 for the longer allele. A marked difference in serum ACE levels was observed between subjects in each of the three ACE genotype classes. Serum immunoreactive ACE concentrations were, respectively, 2993±49, 392.6±66.8, and 494.1±883 ,g/liter, for homozygotes with the longer allele (n = 14), and heterozygotes (n = 37) and homozygotes (n = 29) with the shorter allele. The insertion/deletion polymorphism accounted for 47% of the total phenotypic variance of serum ACE, showing that the ACE gene locus is the major locus that determines serum ACE concentration. Concomitant determination of the ACE genotype will improve discrimination between normal and abnormal serum ACE values by allowing comparison with a more appropriate reference interval. (J. Clin. Invest. 1990Invest. . 86:1343Invest. -1346

No abstract

Factors involved in the pathogenesis of atherosclerosis, thrombosis and vasoconstriction contribute to the development of coronary heart disease. In a study comparing patients after myocardial infarction with controls, we have explored a possible association between coronary heart disease and a variation found in the gene encoding angiotensin-converting enzyme (ACE). The polymorphism ACE/ID is strongly associated with the level of circulating enzyme. This enzyme plays a key role in the production of angiotensin II and in the catabolism of bradykinin, two peptides involved in the modulation of vascular tone and in the proliferation of smooth muscle cells. Here we report that the DD genotype, which is associated with higher levels of circulating ACE than the ID and II genotypes, is significantly more frequent in patients with myocardial infarction (n = 610) than in controls (n = 733) (P = 0.007), especially among subjects with low body-mass index and low plasma levels of ApoB (P < 0.0001). The ACE/ID polymorphism seems to be a potent risk factor of coronary heart disease in subjects formerly considered to be at low risk according to common criteria.

No abstract

The amino-terminal amino acid sequence and several internal peptide sequences of angiotensin I-converting enzyme (ACE; peptidyl-dipeptidase A, kininase II; EC 3.4.15. 1) purified from human kidney were used to design oligonucleotide probes. The nucleotide sequence of ACE mRNA was determined by molecular cloning of the DNA complementary to the human vascular endothelial cell ACE mRNA. The complete amino acid sequence deduced from the cDNA contains 1306 residues, beginning with a signal peptide of 29 amino acids. A highly hydrophobic sequence located near the carboxylterminal extremity of the molecule most likely constitutes the anchor to the plasma membrane. The sequence of ACE reveals a high degree of internal homology between two large domains, suggesting that the molecule resulted from a gene duplication. Each of these two domains contains short amino acid sequences identical to those located around critical residues of the active site of other metallopeptidases (thermolysin, neutral endopeptidase, and collagenase) and therefore bears a putative active site. Since earlier experiments suggested that a single Zn atom was bound per molecule of ACE, only one of the two domains should be catalytically active. The results of genomic DNA analysis with the cDNA probe are consistent with the presence of a single gene for ACE in the haploid human genome. Whereas the ACE gene is transcribed as a 4.3-kilobase mRNA in vascular endothelial cells, a 3.0-kilobase transcript was detected in the testis, where a shorter form of ACE is synthesized.Peptidyl-dipeptidase A (EC 3.4.15.1) plays an important role in blood pressure homeostasis by hydrolyzing angiotensin I, the inactive peptide released after cleavage of angiotensin by renin, into angiotensin II (1). Accordingly, this Zn metallopeptidase is designated angiotensin I-converting enzyme (ACE), although being the same enzyme as kininase II, it is also able to hydrolyze bradykinin and various other peptides (2, 3). This enzyme is a widely distributed peptidase, occurring, for example, as a membrane-bound ectoenzyme on the surface of vascular endothelial cells and renal epithelial cells and as a circulating enzyme in plasma (3-5). We report here the amino acid sequence of ACE as deduced from the nucleotide sequence of DNA complementary to the ACE mRNA.t MATERIALS AND METHODSPurification and Sequencing of ACE and Preparation of Oligodeoxyribonucleotide Probe. The cortex offresh postmortem human kidneys (600 g) was homogenized (54:100, wt/vol) in 20 mM potassium phosphate buffer (pH 8) containing 250 mM sucrose and a mixture of protease inhibitors, cells debris was discarded, and the particulate fraction was sedimented by centrifugation at 105,000 x g for 1 hr. The pellet was resuspended in 200 ml of 150 mM potassium phosphate buffer (pH 8; buffer I) and treated for 18 hr with the detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS, 8 mM; Serva). The supernatant obtained after centrifugation at 105,000 x g for 1 hr was dialyzed extensively against b...

We conducted the present study to determine whether the angiotensin II type I receptor (AT,) gene might be implicated in human essential hypertension by using case-control and linkage studies. The entire coding and 3' untranslated regions of the AT, receptor gene (2.2 kb) were amplified by polymerase chain reaction and submitted to single-strand conformation polymorphism in 60 hypertensive subjects with a familial susceptibility. We identified five polymorphisms (T 573 -»C, A 1062 -*G, A" 6 6^C , G 1 5 "^T, and A' 878 -»G). However, no mutations that alter the encoded amino acid sequence were detected. A case-control study performed on white hypertensive (n=206; blood pressure, 168±16/103±9 mm Hg) and normotensive (n=298; blood pressure, 122±10/75±9 mm Hg) subjects using three of five polymorphisms showed a significant increase in allelic fre-H uman essential hypertension is thought to result from the interaction of environmental and genetic factors, with approximately 30% of the interindividual variability in blood pressure being genetically determined.1 The renin-angiotensin system is an important component of blood pressure regulation, playing roles in saltwater homeostasis and vascular tone, 2 and has been suspected to be involved in hypertension. Indeed, evidence for a genetic linkage of human essential hypertension to the angiotensinogen locus was recently obtained in an extensive collaborative study.3 However, linkage and association studies of the human renin and angiotensin I (Ang I)-converting enzyme loci have given negative results. 49Ang II receptors, which mediate the vasoconstrictive and salt-conserving actions of the renin-angiotensin system, also represent interesting candidate genes for essential hypertension. Two subtypes of cell surface

Pulmonary arterial hypertension (PAH) is a rare disorder with a poor prognosis. Deleterious variation within components of the transforming growth factor-β pathway, particularly the bone morphogenetic protein type 2 receptor (BMPR2), underlies most heritable forms of PAH. To identify the missing heritability we perform whole-genome sequencing in 1038 PAH index cases and 6385 PAH-negative control subjects. Case-control analyses reveal significant overrepresentation of rare variants in ATP13A3, AQP1 and SOX17, and provide independent validation of a critical role for GDF2 in PAH. We demonstrate familial segregation of mutations in SOX17 and AQP1 with PAH. Mutations in GDF2, encoding a BMPR2 ligand, lead to reduced secretion from transfected cells. In addition, we identify pathogenic mutations in the majority of previously reported PAH genes, and provide evidence for further putative genes. Taken together these findings contribute new insights into the molecular basis of PAH and indicate unexplored pathways for therapeutic intervention.

BACKGROUND Pulmonary arterial hypertension is a devastating disease with high mortality. Familial cases of pulmonary arterial hypertension are usually characterized by autosomal dominant transmission with reduced penetrance, and some familial cases have unknown genetic causes. METHODS We studied a family in which multiple members had pulmonary arterial hypertension without identifiable mutations in any of the genes known to be associated with the disease, including BMPR2, ALK1, ENG, SMAD9, and CAV1. Three family members were studied with whole-exome sequencing. Additional patients with familial or idiopathic pulmonary arterial hypertension were screened for the mutations in the gene that was identified on whole-exome sequencing. All variants were expressed in COS-7 cells, and channel function was studied by means of patch-clamp analysis. RESULTS We identified a novel heterozygous missense variant c.608 G→A (G203D) in KCNK3 (the gene encoding potassium channel subfamily K, member 3) as a disease-causing candidate gene in the family. Five additional heterozygous missense variants in KCNK3 were independently identified in 92 unrelated patients with familial pulmonary arterial hypertension and 230 patients with idiopathic pulmonary arterial hypertension. We used in silico bioinformatic tools to predict that all six novel variants would be damaging. Electrophysiological studies of the channel indicated that all these missense mutations resulted in loss of function, and the reduction in the potassium-channel current was remedied by the application of the phospholipase inhibitor ONO-RS-082. CONCLUSIONS Our study identified the association of a novel gene, KCNK3, with familial and idiopathic pulmonary arterial hypertension. Mutations in this gene produced reduced potassium-channel current, which was successfully remedied by pharmacologic manipulation. (Funded by the National Institutes of Health.)