C3AR1 and type 2 diabetes mellitus: The data aligned to the methylation levels of nine hub genes in T2DM were obtained from DiseaseMeth 2.0, indicating significant hypomethylation levels of TYROBP, TLR8, FCER1 G, NCF2, CTSS, FCGR2A, MNDA, and C3AR1 in T2DM.