Germline and somatic variants in DNMT3A and other clonal haematopoiesis of indeterminate potential genes contribute to pulmonary arterial hypertension.

Background And Aims: Multiple germline gene variants promote familial and idiopathic pulmonary arterial hypertension (PAH); however, none are consistently identified in associated PAH with connective tissue disease (APAH-CTD). Moreover, the role of somatic variants in genes mediating clonal haematopoiesis of indeterminate potential (CHIP) in PAH is unknown. Here, somatic and germline DNMT3A variants and CHIP gene variants in PAH were evaluated.

Germline and Somatic Mutations in DNA Methyltransferase 3A Predispose to Pulmonary Arterial Hypertension (PAH) in Humans and Mice: .

Background: Mutations are found in 10-20% of idiopathic PAH (IPAH) patients, but none are consistently identified in connective tissue disease-associated PAH (APAH), which accounts for ∼45% of PAH cases. mutations, a cause of clonal hematopoiesis of indeterminant potential (CHIP), predispose to an inflammatory type of PAH. We now examine mutations in another CHIP gene, , in PAH.

Efficacy of Drpitor1a, a Dynamin-Related Protein 1 inhibitor, in Pulmonary Arterial Hypertension.

Rationale: Dynamin-related protein 1 (Drp1), a large GTPase, mediates mitochondrial fission. Increased Drp1-mediated fission permits accelerated mitosis, contributing to hyperproliferation of pulmonary artery smooth muscle cells (PASMC), which characterizes pulmonary arterial hypertension (PAH). We developed a Drp1 inhibitor, Drpitor1a, and tested its ability to regress PAH.

The Role of Clonal Hematopoiesis of Indeterminant Potential and DNA (Cytosine-5)-Methyltransferase Dysregulation in Pulmonary Arterial Hypertension and Other Cardiovascular Diseases.

DNA methylation is an epigenetic mechanism that regulates gene expression without altering gene sequences in health and disease. DNA methyltransferases (DNMTs) are enzymes responsible for DNA methylation, and their dysregulation is both a pathogenic mechanism of disease and a therapeutic target. DNMTs change gene expression by methylating CpG islands within exonic and intergenic DNA regions, which typically reduces gene transcription.