Parkinson's disease (PD) is a common neurodegenerative disorder with a lifetime incidence of approximately 2 percent; the clinical manifestations of this neurodegenerativedisorder include resting tremor, muscular rigidity, bradykinesia,and postural instability. A relatively specific pathological featureaccompanying the neuronal degeneration is an intracytoplasmicinclusion body, known as the Lewy body. A mutation was identified in the -synuclein gene, which codesfor a presynaptic protein thought to be involved in neuronal plasticity, this mutation may cause a conformational change that renders -synuclein more prone to self aggregation and deposition in Lewy bodies, which finally leads to oxidative stress and misfolding of -synuclein. Parkin gene, mutations in this gene are reported in early autosomal-recessive form of PD, however these mutations do not degenerate Lewy bodies. The Parkin gene product (Parkin) is involved in protein degradation as a ubiquitin protein ligase, the known substrates of Parkin include Pael-R (Parkin-associated endothelin receptor-like receptor), Ubiquitination of Pael-R by Parkin leads to its degradation in the proteasome, however failure to ubiquitinate it leads to death of neuron. The synuclein exists in 3 isoform -syn (chrm 4q21), a 140aa protein, implicated in pathogenesis of PD and related neurodegenerative disorders, it is mainly expressed in brain specifically in neuronal cell bodies and synapses. The 134 aa b-syn (chrm 5q35) is homologous to 14kD bovine phosphoneuroprotein 14; SCNB has been shown to be highly expressed in the substantia nigra of the brain. Recently a new isoform termed g-synuclein (SNCG) or breast cancer gene 1 (BCG1) has been cloned (human 127 aa (chrm 10q23), rat/mouse 123 aa). Higher levels of expression of SNCG have been reported in advanced breast carcinomas. All three synuclein show ~40% identity. Human Gamma synuclein recombinant protein, an acidic neuronal protein of 127aa. It is up regulated in the majority of late-stage breast and ovarian cancers, it promotes cancer cell survival and inhibits stress and chemotherapy drug induced apoptosis by modulating MAP kinase pathways.