In 2013, Kalra et al. [33] studied the correlation between CRP in serum and in CF in patients with chronic periodontitis, with and without diabetes mellitus, compared with healthy individuals; they reported that CRP levels were increased in patients who had both periodontitis and diabetes mellitus, suggesting that the presence of a systemic condition can affect the levels of inflammation mediators, both locally and systemically. The gene discussed is CRP; the disease is cystic fibrosis.