Moreover, the most significant shared down regulated genes between T2D and Smoking: LRRCC1, EPHA7, ARHGAP20, SELL, FLOT1, PCDH18, CFI, ARHGAP11A, CENPH, KRBOX1, MYB, PRIM1, MICA, HMSD, CDCA7, KIFC1, HLA-DPA1, ZNF385D, GPR158, SMN1, HLA-DPB1, MGP, CERS6-AS1, PSMB8, PCYT1B, E2F2, TCF19 and RNVU1-4. The gene discussed is PCYT1B; the disease is type 2 diabetes mellitus.