The aim of this new Core is to provide a repository for mouse models of Parkinson's disease at the UCLA Morris K. Udall Center of Excellence for Parkinson's Disease Research. These mice will then be provided to the research community for scientists who need this valuable resource in their studies. Briefly, two colonies of each genetically altered mouse model will be housed in the vivarial facilities at UCLA. The first colony will consist of a small group of breeders located in a pathogen free barrier facility with extremely limited access. These breeders will be the back-up mice in case the main colony becomes compromised by one of the various mouse infective agents. The second colony for each genetically altered mouse model will be in a barrier facility but with greater access and each colony will be large enough to supply either breeding groups to investigators or small numbers of mice for pilot studies. The UCLA vivarial facilities will provide maintenance support for the colonies. However, the personnel in charge of administering the colonies, breeding the mice and shipping the mice to investigators will be the Mouse Repository Core personnel. Permission of individual investigators to utilize mice from this facility will be obtained via agreements with the Neurodegenerative Group of the NINDS and the investigators who generate the mouse models and be limited to investigators at academic and non-profit institutions. The UCLA facility will only be permitted to supply mice when such agreements are on file with NINDS staff and investigators/institutions responsible for the generation of the mice.