Both GDF-15 (adj OR: 1.0003, 95%CI: 1.0001–1.0005, P = 0.017) and hepcidin (adj OR: 1.003, 95%CI: 1.0004–1.0055, P = 0.023) were associated with iron deficiency anaemia after multiple linear regression modelling. The gene discussed is HAMP; the disease is Iron deficiency anemia.