1. 1) DDBJ (DNA Data Bank of Japan), http://www.ddbj.nig.ac.jp/ (referred on May 20, 2003).
2. 2) GenBank, http://www.ncbi.nlm.nih.gov/Genbank/index.html (referred on May 20, 2003).
3. 3) Ensembl, http://www.ensembl.org/ (referred on May 20, 2003).
4. 4) GenBank Statistics, http://www.ncbi.nlm.nih.gov/Genbank/genbankstats.html (referred on May 20, 2003).
5. 5) PIR (Protein Information Resource), http://pir.georgetown.edu/ (referred on May 20, 2003).