TPMT*32 is assigned uncertain function based on inadequate evidence. Erythrocytes from a patient genotyped TPMT*1/*32 exhibited intermediate enzymatic activity and the patient's 6-TGN plasma concentration was 694 pmol/8×108 RBCs after receiving 75 mg/m2 6-MP (23252716). An additional patient genotyped TPMT*1/*32 received 43 mg/m2 6-MP, which is 57% of the standard dose, and the patient exhibited a 6-TGN plasma concentration of 1257 pmol/8×108 RBCs (25564374). Erythrocytes from the second patient exhibited normal TPMT enzymatic activity (25564374). Four out of ten variant effect predictors tested by CPIC staff predict that the TPMT*32-defining SNV, c.340G>A (p.E114K), impairs protein function.