USP38 and essential hypertension: This gene-based association approach with tissue specificity has a lower multiple-testing burden [68] and has identified three key genes in essential hypertension: potassium two-pore domain channel subfamily K member 3 (KCNK3), glutamyl aminopeptidase (ENPEP), and ubiquitin-specific peptidase 38 (USP38) [67].