Pharmacogenetics of azathioprine

Azathioprine is a thiopurine employed as an immunosuppressive and anti-inflammatory agent, it might elicit adverse drug reactions in patients who have not been tested before the administration. AZA is metabolized by different enzymes and those that can exhibit lower activity and afterwards bring to toxic effects are essentially two: TPMT (Thiopurine-methyl-transferase) and NUDT15 (Nudix hydrolase 15). Therefore, preemptive genotyping is crucial in the choice of reducing the dosage or even using an alternative treatment. Even though the traditional medical approach is still used for the treatment of numerous diseases, the personalized one is rising more and more and it aims to tailor the treatment to the patient relying on its genetic profile; this is the so called personalized medicine (also known as precision medicine) and it proceeds by clustering the patients into different groups and by giving them a different treatment based on the genetic analysis. Different techniques for patients' genotyping have been exploited in the years such as RFLP assay and melting curve analysis; nowadays they are not as efficient as the newer ones, in terms of costs and time required, which have an automatic interpretation of results: the TaqMAMA Real-Time PCR System and the New Allele-Specific Real-Time PCR System.