PCSK9 and periodontitis: Analysis of variables showed that 11 genes (ARHGAP15, FFAR2, ACSL5, SLAMF7, NLRP12, CCRL2, HSH2D, CSF3R, DBI, CEACAM3 and NCR1) had significant contribution to the RF model in PCOS (Fig. 2C) which were candidate hub genes 1, and 20 genes (LYN, P2RY13, CLEC12A, PRF1, GPR65, CEACAM3, OSM, PCSK9, ALOX5AP, LILRA2, FPR1, SLC11A1, CCRL2, FCGR2A, NCF2, CXCR1, PRAM1, NLRP12, ACSL5, and VNN2) had the highest effect in the RF model in periodontitis (Fig. 2D) which candidate hub genes 2.