FPR3 and diabetes mellitus: Epigenetic dysregulation of DNA in OSAS was shown by aberrant methylation of the formyl peptide receptor (FPR) 1, 2, 3 genes, and FPR1 overexpression and the deficiency of FPR2 and FPR3 were associated with OSAS and its severity as well as with the development of diabetes mellitus and cardiovascular diseases.