Finally, the expression of RGS2 was lower in total periodontitis tissues compared with total control tissues (RME = 0.24, P-value = 0.01), affected tissues obtained from men compared with male control tissue (RME = 0.16, P-value = 0.02), and total blood samples of affected individuals compared with controls (RME = 0.42, P-value = 0.05). Here, RGS2 is linked to periodontitis.