DNA and RNA fractions have been isolated from whole blood, serum, plasma, the surface of blood cells, and urine from both healthy persons and patients. Specific fragments have been identified as being related to particular disorders, for example, diabetes, cancer, myocardial infarction, and stroke. The ability to isolate these fractions and assess their relationship to specific diseases makes early noninvasive diagnosis possible. This volume reports on the most recent progress in this field, including chapters on developing protocols for nucleic acid extraction, determining the origin of the circulating nucleic acids, the capacity of these nucleic acids to enter cells and exhibit biological activity, isolating and testing fetal cells from maternal blood, and discussing the clinical implications of these discoveries and developing the techniques that will bring them into clinical application. NOTE: Annals volumes are available for sale as individual books or as a journal. For information on institutional journal subscriptions, please visit www.blackwellpublishing.com/nyas. ACADEMY MEMBERS: Please contact the New York Academy of Sciences directly to place your order (www.nyas.org). Members of the New York Academy of Science receive full-text access to the Annals online and discounts on print volumes. Please visit http://www.nyas.org/MemberCenter/Join.aspx for more information about becoming a member