Variant in a common odorant-binding protein gene is associated with bitter sensitivity in people.

Deeper understanding of signaling mechanisms underlying bitterness perception in people is essential for designing novel and effective bitter blockers, which could enhance nutrition and compliance with orally administered bitter-tasting drugs. Here we show that variability in a human odorant-binding protein gene, OBPIIa, associates with individual differences in bitterness perception of fat (oleic acid) and of a prototypical bitter stimulus, 6-n-propylthiouracil (PROP), suggesting a novel olfactory role in the modulation of bitterness sensitivity.