4 of 10 tested odors were found to have genetic variants that cause people to smell them differently Genetic differences cause us to experiences scents and tastes in different ways.
There are some smells we all find revolting. But toward a handful of odors, different people display different sensitivities—some can smell them, while some can't, or some find them appealing, while others don't. A pair of studies appearing online on August 1 in the journal Current Biology, a Cell Press publication, now identifies the genetic differences that underpin the differences in smell sensitivity and perception in different individuals. The researchers tested nearly 200 people for their sensitivity for ten different chemical compounds that are commonly found in foods. They then searched through the subjects' genomes for areas of the DNA that differed between people who could smell a given compound and those who could not. This approach—known as a genome-wide association study—is widely used to identify genetic differences.
Not everyone gets the same thrill from the scent of an apple or blue cheese.
The researchers, led by Sara Jaeger, Jeremy McRae, and Richard Newcomb of Plant and Food Research in New Zealand, found that for four of the ten odors tested, there was indeed a genetic association, suggesting that differences in the genetic make-up determine whether a person can or cannot smell these compounds. The smells of these four odorants are familiar, for those who can smell them (though their names may not be): malt (isobutyraldehyde), apple (β-damascenone), blue cheese (2-heptanone), and β-ionone, which smells floral to some people and is particularly abundant in violets.
These researchers haven't tested many scents yet and expect more genetic differences in sense of smell will be found for other scents.
Genes cause differences in esthetic experiences. I bet there are genetic variants for whether various sounds are pleasant or irritating too. A small number of women tetrachromats who see 4 primary colors because of X chromosome mutations that give their eyes cones that absorb at a 4th frequency.
Think about what the world will be like in a few decades when prospective parents become able to choose genetic variants that will determine the esthetic experience of their offspring.
|Share |||Randall Parker, 2013 August 01 10:02 PM|