The Bioinformatics Institute, Agency for Science, Technology and Research, Singapore and Department of Surgery, Faculty of Medicine, National University of Singapore, Singapore

Correspondence and requests for reprints to Adrian Mondry, The Bioinformatics Institute, Agency for Science, Technology and Research, 30 Biopolis Street, 07-01 Matrix Building, Singapore 138671, Singapore. Tel: +65 64788383; fax: +1 65 64789048; e-mail: [email protected]