aGenetic Health Queensland, Royal Brisbane and Women's Hospital bRoyal Children's Hospital, Brisbane, Queensland, Australia Correspondence to Associate Professor Julie McGaughran, MD, Royal Brisbane and Women's Hospital, Herston, Brisbane 4029, Australia Tel: +61 7 3636 1686; fax: +61 7 3636 1987; e-mail: [email protected] Received 6 January 2009 Accepted 19 February 2009