In conclusion, we evaluated whether four novel cytokines (chemerin, omentin-1, YKL-40, and sCD26) secreted from different origins in type 2 diabetic patients were associated with CAD, and found that only serum YKL-40 levels were markedly elevated in patients with type 2 diabetes patients with suspected CAD on cCTA compared to patients with no evidence of CAD. This evidence concerns the gene RARRES2 and type 2 diabetes mellitus.