TAGLN2 and pulmonary arterial hypertension: This study, through MR and mediation analysis, elucidated the complex mechanism by which DNA methylation sites (cg13892570 and cg16107628) influence the levels of HLA DR+ monocytes, cysteinylglycine disulfide, and eicosenedioate by regulating the expression of the succinylation-related gene TAGLN2, ultimately modulating the risk of PAH.