In the December issue of UF Health Personalized Medicine Program's e-newsletter, SNPits, a recent study by Lee, et al. entitled "DPYD variants as predictors of 5-fluorouracil toxicity in adjuvant colon cancer treatment" is reviewed. The authors find a statistically significant association between DPYD*2A and rs67376798 (DPYD D949V) and increased toxicity in patients treated with 5-fluorouracil-based combination chemotherapy. This large randomized phase III trial is important evidence supporting the clinical applicability of these variants.
CPIC's dosing recommendations for 5-FU dosing with DPYD variants is found on PharmGKB here.