A total of 142 regular MHD patients (January 2022–June 2023) were divided into renal anemia group (Hb < 110 g/L, n = 75) and non-anemia group (Hb ≥ 110 g/L, n = 67) per 2017 Kidney disease guidelines; 74 healthy controls were included. Here, GSTM1 is linked to anemia (phenotype).