gamma-synuclein(Originally known as a breast cancer specific gene product, BCSG1) is an acidic neuronal protein of 127 amino acids. The protein coding region of gamma-synuclein was amplified by RT-PCR and cloned into an E.coli expression vector. gamma-synuclein was overexpressed in E. coli and purified to apparent homogeneity by taking advantage of the thermosolubility of the protein and by using conventional column chromatography techniques.