Four genes (CDH2/PCDHB10/PCDHB11/PCDHB9) in the anterior circulation-left hemisphere subgroup, 8 genes (CDH2/PCDHB10/PCDHB11/PCDHB14/PCDHB16/PCDHB3/PCDHB6/PCDHB9) in the anterior circulation-right hemisphere subgroup and 4 genes (CDH2/PCDHB10/PCDHB11/PCDHB9) in the posterior circulation subgroup showed differences after adjusting for smoking, drinking, history of hypertension and diabetes, and blood lipid levels (p < 0.05, Table 6). The gene discussed is PCDHB9; the disease is diabetes mellitus.