TF and osteoarthritis: Our findings revealed a causal link between ferritin and an increased risk of osteoarthritis, a causal association between serum iron and TSAT levels and a reduced risk of RA, a causal association between serum iron and an increased risk of AS, a causal relationship between serum iron and TSAT levels and an elevated risk of gout, and a causal correlation between transferrin and a decreased risk of gout.