What this means

TAS2R38 is a bitter taste receptor that detects PTC (phenylthiocarbamide) and the related compound PROP — molecules chemically similar to the glucosinolates in cruciferous vegetables like broccoli, kale, and Brussels sprouts. Three common amino acid changes (P49A, A262V, V296I) cluster into two main haplotypes: PAV ("taster") and AVI ("non-taster"). About three quarters of people worldwide carry at least one PAV copy. Tasters often find these vegetables more bitter; non-tasters often shrug.

TAS2R38 is a bitter taste receptor on your tongue — it picks up bitter compounds in foods like Brussels sprouts, kale, broccoli, dark beer, and tonic water. Different versions of this gene change how strongly the receptor fires, and that changes how bitter those foods taste to you. About three out of four people worldwide carry at least one "taster" version of this gene.

Caveats

• Cooking, fat, salt, and what you grew up eating all dampen the effect.
• Bitter perception involves dozens of receptors — this is just one common one.
• Taster status does not reliably predict who likes or dislikes any given food.
• Effect is well-replicated but the magnitude varies between studies.

References

• Kim et al. — Positional cloning of the human quantitative trait locus underlying taste sensitivity to PTC (Science, 2003)
• Bufe et al. — The molecular basis of individual differences in phenylthiocarbamide and propylthiouracil bitterness perception (Current Biology, 2005)