NCG is divided into four sections: (i) the gene summary table, which allows the conversion between different gene and protein identifiers, using the Entrez ID as primary key; (ii) the duplicability table, which includes all results of the BLAT alignments on the human genome; (iii) the orthology table, which stores the orthology relationships; and (iv) the network table, which includes the network properties for each protein. The data collected in NCG are stored in a MySQL database. The web interface to interrogate the database is built in Perl.
