Let's talk about Bitter Taste

Why are some people more prone to sensing bitter tastes?

Taste buds are covered with tiny molecular sensors, called “taste receptors,” that specialize in detecting the five basic tastes: sweet, salty, sour, bitter, and umami (a savory, meat-like taste). The types of taste receptors you have determine what tastes you can, or cannot, detect in foods. Some vegetables, like broccoli and brussels sprouts, contain naturally bitter chemicals. Scientists think some people may be unable to detect these bitter chemicals based on what taste receptors they have.

Where do genetics come in?

The TAS2R38 gene contains instructions for a protein, or taste receptor, that can detect the bitter chemical called “PTC.” PTC isn’t usually found in the human diet, but it is similar to chemicals present in vegetables like broccoli and brussels sprouts. People with the G variant have a taste receptor that can detect these PTC-like chemicals. This means people with the G variant may taste bitterness in these foods and avoid them all together.

Did you know?

Giant pandas cannot detect umami (a savory, meat-like taste) because their umami taste receptors don’t work properly. This means they can’t taste meatiness, and don’t show a preference for meat. Scientists believe this explains their strict bamboo diet, despite being closely related to other carnivores.

Explore more

Find out if you’re more likely to be able to detect bitter tastes based on your genetics with the 23andMe Bitter Taste report, which you can get with one of 23andMe’s services. Order a kit to learn more.

References

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Callaway E. (2012). “Evolutionary biology: the lost appetites.” Nature. 486(7403):S16-7. 

Genick UK et al. (2011). “Sensitivity of genome-wide-association signals to phenotyping strategy: the PROP-TAS2R38 taste association as a benchmark.” PLoS One. 6(11):e27745. 

Hayes JE et al. (2008). “Supertasting and PROP bitterness depends on more than the TAS2R38 gene.” Chem Senses. 33(3):255-65. 

Hayes JE et al. (2013). “Do polymorphisms in chemosensory genes matter for human ingestive behavior?” Food Qual Prefer. 30(2):202-216. 

Kim UK et al. (2003). “Positional cloning of the human quantitative trait locus underlying taste sensitivity to phenylthiocarbamide.” Science. 299(5610):1221-5. 

Lindemann B. (2001). “Receptors and transduction in taste.” Nature. 413(6852):219-25. 

Mennella JA et al. (2005). “Genetic and environmental determinants of bitter perception and sweet preferences.” Pediatrics. 115(2):e216-22. 

Nei M et al. (2008). “The evolution of animal chemosensory receptor gene repertoires: roles of chance and necessity.” Nat Rev Genet. 9(12):951-63. 

Shi P et al. (2006). “Contrasting modes of evolution between vertebrate sweet/umami receptor genes and bitter receptor genes.” Mol Biol Evol. 23(2):292-300.