What one person perceives as a heavenly perfume may be an intolerable stench for another. New research finds that no two people experience scent in exactly the same way, MedicalExpress reports. So there's a lot of room for interpretation about where on a particular odor falls on the spectrum of roses to trash.
The way a person perceives smells comes down to her particular arrangement of amino acids. A difference of a single amino acid on one gene can cause that person to experience a smell differently than someone with another amino acid. Around 400 genes code for smell, MedicalExpress explains, and on those hundreds of genes, there are around 900,000 potential variations.
Duke University researchers compared scent receptors among people and found that they tend to be about 30 percent different from person to person. To further explore this question, lead researcher Hiroaki Matsunami cloned 500 scent receptors from 20 people. Each of those receptors were slightly different, on the order of an amino acid or two. When Matsunami exposed the receptors to 73 different common odor molecules, he was able to identify 27 receptors that responded quite differently to one or more of those smells.
"We found that individuals can be very different at the receptor levels, meaning that when we smell something, the receptors that are activated can be very different (from one person to the next) depending on your genome," Matsunami said.
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