In this study, first we observed the alteration of the specific marker of PD such as TH, that is the enzyme responsible for catalysing the conversion of L-tyrosine to dihydroxyphenylalanine (DOPA), a precursor for dopamine, and of DAT a member of a large family of Na+-Cl−lCember of aopamine transporters. The gene discussed is SLC6A3; the disease is Parkinson disease.