A genetic variation that may indicate a patient’s risk of developing a potentially life-threatening blood disorder if exposed to certain pharmaceutical therapies or chemicals is one of several medical discoveries scientists at Quest Diagnostics will present during the 51st American Society of Hematology (ASH) Annual Meeting and Exposition, December 5-8, 2009, in New Orleans, LA.

In 17 oral, poster and abstract presentations, the Quest Diagnostics scientists will also describe novel mutations, discoveries and tests that may lead to extensions to the company’s proprietary Leumeta(TM) portfolio of blood-plasma tests for leukemia and lymphoma. Leumeta tests identify genetic markers that can help physicians detect disease, predict therapy response and monitor disease progression using plasma rather than cells, replacing, in some cases, the need for painful bone-marrow biopsies.

In addition, scientists will report on the performance of a diagnostic technique for identifying if a patient with heparin-induced thrombocytopenia (HIT) will also experience HIT when treated with a synthetic form of heparin, fondaparinux sodium (ARIXTRA®). HIT is an immune reaction experienced by some patients after exposure to the blood thinning drug heparin that can promote the formation of potentially life threatening blood clots (abstract number 1319).

For a list of Quest Diagnostics presentations, refer to Quest’s Web site

"As a leader in diagnostics in hematologic cancers and other blood disorders, our goal is to bridge the divide between scientific discovery and clinical need with novel, quality diagnostics," said Jon R. Cohen, M.D., chief medical officer and senior vice president, Quest Diagnostics. "Our scientists’ research presented at ASH 2009 expands the growing body of knowledge of the genetic and biological factors implicated in blood diseases. It also promotes our development of new diagnostics, including in our Leumeta(TM) family, for aiding clinical care of patients."

An example of the potential clinical value of the company’s scientific research is a study that found that a single nucleotide polymorphism (SNP), a variation in a DNA sequence, of the erythropoietin (EPO) gene is associated with the development of the blood disorder myelodysplastic syndrome (MDS), a potentially life-threatening illness for some patients (abstract number 3825).

"MDS is well documented to develop after exposure to toxic agents, including chemotherapy and radiation therapy for cancer, in some patients," said Maher Albitar, M.D., medical director and chief of Research and Development, Hematology and Oncology, Quest Diagnostics Nichols Institute, the esoteric research, development and testing operation of Quest Diagnostics. "While additional investigation is required, our findings suggest the potential clinical value of detecting a specific EPO gene polymorphism in high-risk individuals. For instance, patients with this specific polymorphism could store stem cells prior to beginning chemotherapy, so that if they develop MDS, they could undergo a bone marrow transplant using their own healthy cells at a later time."

Dr. Albitar continued: "We are also excited about our research of the Ki-67 protein (abstract numbers 1261 and 3104), MPL gene (abstract number 1891) and BCR-ABL1 protein (abstract numbers 1107 and 2179), among others. These studies underscore the clinical value of our proprietary Leumeta plasma-based technique, while also providing the basis for expanding this test portfolio with new diagnostic tests."

The company’s Leumeta family of plasma-based molecular tests were the first available to doctors for directly identifying markers of hematologic cancers in blood plasma rather than painfully extracted bone marrow biopsies when launched in 2006. Since that time, the Leumeta test family has grown to include more than 24 tests.

Source: Quest Diagnostics