In addition, we used RT-PCR to detect the expression of several DEG genes in T2DM and RC, and the results showed that CDH3, CHGA, ESR1, SCG3, SP1 and SYP genes were the highest in patients with comorbidities, while compared with normal healthy people, the expression of CDH3, CHGA, ESR1, SCG3, SP1 and SYP genes was higher. This evidence concerns the gene CHGA and type 2 diabetes mellitus.