Once we had identified methylated CpGs that expressed in control blood, versus blood from PAH patients with or without TET2 mutation, we aggregated them into differentially methylated regions (DMR) and compared the following three groups: ([Control vs. PAH TET2 mutation], [Control vs. PAH No mutation], and [PAH TET2 mutation vs. PAH No mutation]). This evidence concerns the gene TET2 and pulmonary arterial hypertension.