Mayo Clinic technician Paul Heimgartner performs computer analyses of “genetic signatures” to predict how individuals metabolize and respond to warfarin.

Mayo Clinic technician Paul Heimgartner performs computer analyses of “genetic signatures” to predict how individuals metabolize and respond to warfarin, which in turn help doctors find the correct dosage for the individual, 2006. The cost-effectiveness of DNA testing in assessing dosage is an open debate among doctors and insurers despite the difficulty of dosing and common complications that occur with the drug.

AP Photo/Christina Paolucci