Using prism8.0 software, a violin plot comparing methylation levels of the promoter region of selenoprotein gene DIO3-FA27 in patients with HF and healthy control groups was fitted, indicating that a nonsignificant difference was observed in methylation fragments in the promoter region of DIO3-FA27 between patients with HF and healthy controls (P > 0.05, Fig. 2). Here, SELENOS is linked to hydrops fetalis.