The tumor suppressor gene database (TSGDB) contains updated information on 174 tumor suppressor genes and putative tumor suppressor genes from human beings and other organisms. Data are collected from publications and publicly available databases including NCBI, OMIM, GeneCard, SOURCE and Swiss-Prot. This database is to help people in the cancer research and/or treatment areas to get the related information rapidly. Users can view information on an individual gene, or query for genes by using gene features which are related to the tumor suppressor genes.    To query for gene(s), users can input more than one keywords in each feature except features source organism and chromosome number.  When querying with protein size, use can put the number of amino acids or put a number range of amino acids, e.g., >=1800 or 220-280, etc.