Erythrocytosis, a condition marked by the overproduction of red blood cells (RBCs), can be either congenital or acquired. Erythropoietin (EPO), the primary hormone regulating RBC production, is controlled by a tightly regulated negative feedback loop. Under hypoxic conditions, the EPO promoter is activated, leading to increased transcription of the EPO locus resulting in increased production of EPO and subsequent rise…