San Francisco, CA, April 26th, 2007 -- XDx, a molecular diagnostics company, today announced its AlloMap molecular expression test will be the subject of presentations and discussions at the 27th Annual Meeting and Scientific Sessions of the International Society for Heart and Lung Transplantation (ISHLT) at the Hilton San Francisco.

Data presented at the ISHLT sessions demonstrates that AlloMap testing may help reduce immunosuppression without the need for invasive biopsies and may allow for prediction of future occurrence of cardiac allograft rejection.

"The data being presented point to the potential clinical utility of molecular expression testing in monitoring rejection based on gene-expression profiling," said Mario C. Deng, M.D., director of Cardiac Transplantation Research, Columbia University Medical Center/New York Presbyterian Hospital, and co-principal investigator in the Cardiac Allograft Gene Expression Observational (CARGO) study. "The fact that we can accomplish this non-invasively, without requiring a routine biopsy, is likely to impact the care and quality of life of many patients who have undergone heart transplantation."

In separate studies, recent data from the Lung Allograft Rejection Gene expression Observation (LARGO) study provides the first confirmation that a non-invasive blood test can detect organ rejection in lung transplant patients.