Supporting this hypothesis, constitutive ERFE-knockout mice with CKD (EKO-CKD) treated with the HIF prolyl hydroxylase inhibitor vadadustat — an agent used to treat CKD-associated anemia — displayed significantly lower BUN and serum creatinine levels compared with vehicle-treated EKO-CKD mice (29). The gene discussed is ERFE; the disease is anemia (phenotype).