Ever wondered why some people love the stinky cheeses that many find odious? It’s probably in our genes, say researchers from Plant and Food Research in New Zealand. They have discovered genetic differences to account for variations in people’s perception of smells.

A pair of studies recently published online in the journal Current Biology had researchers testing almost 200 people for their receptiveness to ten chemical compounds commonly found in food. The researchers then conducted a genome-wide association study, through which they analyzed the subjects’ genomes in search of DNA differences between the ones who could and could not smell each compound.

Of the ten compounds, researchers found four that signaled a genetic connection for how the subjects perceived the smells:

  • Isobutyraldehyde (malt)
  • β-Damascenone (apple)
  • 2-Heptanone (blue cheese)
  • β-Ionone (roses)

The study found that people who have a good nose for roses are also blessed with a strong sense of smell for food and drink. It found that individuals carrying genotypes for β-Ionone sensitivity in particular are better able to distinguish between food and drink smells in general.

The researchers note that people who are sensitive to the roses compound typically describe the smell as fragrant or floral, while the less sensitive may not find it quite as pleasant, describing it as sour or pungent.

Jeremey McRae, one of the scientists involved with the study, says:

We were surprised how many odors had genes associated with them. If this extends to other odors, then we might expect everyone to have their own unique set of smells that they are sensitive to.

These smells are found in foods and drinks that people encounter every day, such as tomatoes and apples. This might mean that when people sit down to eat a meal, they each experience it in their own personalized way.”

A clue as to which genes drive abilities to distinguish odors came to the researchers when they noticed that the genetic variants were located in or near genes that encode olfactory receptors. These receptors are on the surface of sensory nerve cells in our nose. The researchers found that a specific genotype they identified – rs6591536 – influences the associations we have with food on an emotional level. This could explain differences in food and product choices, they say.

When McRae and his colleagues looked at differences in olfactory sensitivities across the world, however, they did not find an indicator of any sort of regional difference. So choices in foods and beverage across different countries are more an indicator of cultural, rather than genetic factors.