CYP2C9*35 is assigned no function based on limited evidence in one heterozygous subject and in vitro studies. CYP2C9*35 was first described in a patient requiring a very low weekly warfarin dose of 2.25mg (2145143). No variant was observed in VKORC1 or CYP4F2 in this patient and a subsequent in silico study showed a decreased interaction with reductase resulting in impaired enzyme activity. In vitro studies similarly found CYP2C9*35 demonstrated no enzyme activity with warfarin, tolbutamide, and diclofenac substrates (23752738, 24322786). Therefore, consensus among experts was no function with an activity value of 0 based on limited evidence as it was determined the phenotypes containing this allele would be clinically distinct from phenotypes comprising normal and decreased function alleles.