Update of the human MitBASE database

Human MitBASE is a database collecting human mtDNA variants. This database is part of a greater mitochondrial genome database (MitBASE) funded within the EU Biotech Program. The present paper reports the recent improvements i n data structure, data quality and data quantity. As far as the database st ructure is concerned it is now fully designed and implemented. Based on the previously described structure some changes have been made to optimise bot h data input and data quality. Cross-references with other bio-databases (E MBL, OMIM, MEDLINE) have been implemented. Human MitBASE data can be querie d with the MitBASE Simple Query System (http://www.ebi.ac.uk/htbin/Mitbase/ mitbase.pl) and with SRS at the EBI under the 'Mutation' section (http://sr s.ebi.ac.uk/srs5/). At present the Human MitBASE node contains similar to 5 000 variants related to studies investigating population polymorphisms and pathologies.