Patients with the rs1801133 AA genotype and cancer who are treated with methotrexate may be at increased risk of toxicity as compared to patients with the AG or GG genotype. However, conflicting evidence has been reported. Other genetic and clinical factors may also influence risk of toxicity following methotrexate treatment. This drug-variant pair has been assigned a 鈥渘o recommendation鈥?by DPWG, as it was determined to be not clinically actionable.