α-Synuclein BAC transgenic mice as a model for Parkinson's disease manifested decreased anxiety-like behavior and hyperlocomotion

α-Synuclein (α-syn), the main component of Lewy bodies, was identified as a genetic risk factor for idiopathic Parkinson's disease (PD). As a model for PD, we generated human α-syn bacterial artificial chromosome transgenic mice (BAC tg mice) harboring the entire human α-syn gene and its gene expression regulatory regions. The α-syn BAC tg mice manifested decreased anxiety-like behaviors which may reflect non-motor symptoms of early PD, and they exhibited increased SERT expression that may be responsible for decreased anxiety-like behaviors. Our α-syn BAC tg mice could be a valuable tool to evaluate α-syn gene dosage effects in vivo.