The expression analysis was executed only on 40 gene spots by excluding 6 genes such as GCSL, FLJ21936, DMRT3, AKR1CL2, UNC5A and UNC5B. The result shows the moderate down regulation of CAT, PDHB, NPFF, TMEM16A, UNC5C, FGF13, JUN and up regulation of INSR, THEG, NOS1, FAM48A, PTPRC, OGDH, SYT1, FGF2 and SST genes in cellular blood of PD. This evidence concerns the gene CAT and Parkinson disease.