A more recent second meta-analysis [34], which included 9 studies with a total of 1305 RA patients and 504 controls, yielded conclusive evidence of a statistically significant increase in serum concentrations of DKK-1 in patients with RA that contribute to the uncoupling between bone resorption and new bone formation at a systemic level. The gene discussed is DKK1; the disease is rheumatoid arthritis.