This result signifies that the patient has one copy of an uncertain/unknown function allele and one copy of a no function allele. Based on the genotype result this patient has a priority result (TPMT possible intermediate metabolizer) because their activity is not likely to be any higher than that of an intermediate metabolizer; if the uncertain/unknown function allele is also low, activity may be even lower than that of an intermediate metabolizer. This patient may be at risk for an adverse reactions to medications that are metabolized by TPMT (eg. thiopurines). To avoid an untoward drug response, dose adjustments or alternative therapeutic agents may be necessary for medications metabolized by TPMT. However, thiopurines can be affected by a patient's TPMT and NUDT15 phenotype. Please consult a clinical pharmacist for more information about how TPMT and NUDT15metabolic status influences drug selection and dosing.