D850 Nucleic Acids Research, 2009, Vol. 37, Database issue common genes and those unique in each set. One can thus pose the question, ‘Which are the common and diﬀering genes found to encode the proteins of the NRC/MASC and post-synaptic density?’ Complementing the text-searching abilities of G2Cdb, one can browse the contents of the database by clicking the various links available under ‘Database’ (on the menu present on the left of all the G2Cdb pages) and in the ‘Top Searches’ links. Examples are ‘Gene Lists’, ‘Human Disease’ and ‘Genes shown to aﬀect long-term potentia- tion (LTP)’. SOFTWARE IMPLEMENTATION G2Cdb is implemented in a relational database manage- ment system (MySQL) in a schema with about 70 tables in which all the biological information and related controlled vocabularies (CVs) are stored. The database back-end is accessed by an object-orientated Perl API, together with an extensive set of Perl scripts for loading the database. These automated loading scripts integrate our curated lit- erature datasets and those obtained from external resources and perform quality control (QC) checks. The G2Cdb website is driven by a set of complementary CGI scripts. The principal objects stored by G2Cdb are genes, alleles, genetically modiﬁed mouse lines, phenotyping experiments and diseases. The API allows one to create, link, store and retrieve these objects in a high-level manner (independent of the underlying SQL) making it straight- forward to implement quite sophisticated analyses. Generic mechanisms exist to attach synonyms, textual notes, literature citations, external databases’ cross- references and binary ﬁles (such as media ﬁles or pdfs) to the core database objects, and to validate object attri- butes with CVs. The website also supports secure login (by single sign-on) should this be required. The software package comprising G2Cdb will be useful to other investigators working in research ﬁelds outside of cognition who have the need to integrate similar types of data from genomics and experimental genetics (genetically altered mice and phenotyping experiments) with disease and mutation information from human genetics studies. In common with other Wellcome Trust-funded infor- matics initiatives, the software is open source, and is avail- able free of charge under the terms of the Perl Artistic License (by request to webmaster@genes2cognition.org). The majority of programmes and modules are documen- ted with embedded Perl documentation (POD) and the schema and API are designed very much in keeping with those of Ensembl, so bioinformaticians familiar with this project should ﬁnd it straightforward to employ the system. new synapse proteomic proﬁling datasets as they become available and continue our text mining and literature cura- tion, focussing on extending the set of genes for which we have curated synaptic plasticity and behavioural studies in genetically modiﬁed mouse models. Similarly, we will con- tinue to survey the human genetics literature for mutations in the human orthologues of these genes and their associa- tion to disease. The G2C research programme and other large-scale research programmes will provide major volumes of data to G2Cdb. The longer term objective is to provide comprehensive information on all synapse pro- teins across a wide range of phenotypes, functions and species. DISCUSSION Driven by the experimental progress in synapse proteo- mics and functional studies of these proteins, we identiﬁed a need for a specialist database for the organization and function of the synapse proteome. This includes capturing detailed information from a number of sources of experi- mentally validated results, expert curated information from the literature and links to related external databases. Importantly, G2Cdb provides a mechanism for the eﬀec- tive re-use and analysis of a range of datasets that are expensive to curate/produce by the wider community. The synapse proteome datasets that G2Cdb provides thus oﬀer a basis for future research in synapse biology and provide useful information on brain diseases. A major application of G2Cdb will be the assembly of molecular networks of the synapse proteome. These include transcriptional, protein interaction and phosphor- ylation networks. Combining this with phenotypic data on speciﬁc proteins in electrophysiology and behaviour from mice, and human disease information will be useful for the systems biology of the synapse. Toward the public understanding of science and the education of school and undergraduates, we are collabor- ating with the Dolan DNA Learning Centre at Cold Spring Harbor Laboratory to provide G2Cdb in a format of use to school and college students. An educa- tional website (www.g2conline.org) will cover a broad range of educational material on the subjects of genes and behaviour including novel network representations of the G2Cdb datasets. ACKNOWLEDGEMENTS The authors would like to thank Phil Elliot and Keri-Lee Page for their contributions of data to G2Cdb and Lianne Stanford for critical review of the article. DATA UPDATES We currently update G2Cdb 2–4 times a year. At these times we release newly incorporated data, make improve- ments to the website to support retrieval of the new data types and generally improve site usability. We plan to load FUNDING Genes to Cognition Programme (Wellcome Trust). Funding for open access charges: Wellcome Trust. Conﬂict of interest statement. None declared.