A study on the DNA methylation profile of the interleukin 6 (IL-6) gene promoter in patients with RA, patients with chronic periodontitis, and healthy controls found that the methylation levels of a specific CpG site were significantly lower in RA and chronic periodontitis patients than in controls, leading to increased levels of serum IL-6 [9]. The gene discussed is IL6; the disease is rheumatoid arthritis.