MR analysis identified significant causal associations between the genes implicated in BW loss (ADD3, HSPA12A, SLC18A2, PDZD8, DUSP5, CASP7) as well as EF% and LV volumes (GPC6, UGGT2, SLAIN1, POU4F1, MBNL2) in BXD mice post-DOX and heart failure (HF) outcomes in humans. The gene discussed is POU4F1; the disease is hydrops fetalis.