Hosted by Sandra Tsing Loh, The Loh Down on Science is a fun way to get your daily dose of science plus a dash of humor in less than two minutes.
Hosted by Sandra Tsing Loh
Airs Weekdays 2:31, 3:31 and 5:49 a.m.

Selfish Scents

Hey, listeners, do you relish your aroma?

This is Sandra Tsing Loh, with the Loh Down on Science, suspecting that you do.

German scientists say we all do. The reason? Proteins that make up the major histocompatibility complex, or MHC. Unique MHC combinations personalize each human's cells; that way, our immune systems know which cells are ours, and which are foreign. Animals can detect each other’s MHC type by scent. Can humans do the same? 

To tackle that question, the German team applied several synthesized MHC proteins to volunteers’ skin. They then told them to take a whiff. Well? When asked which they preferred, people unknowingly chose the replica of their own MHC type.

Turns out, deep down we recognize our MHC type. So much so, that when sniffing it, MRI scans reveal activation in a brain region unaffected by other types.

There’s still much more to learn about the role MHC types play in human interactions.                 
But in the meantime, MHC puts the smell in self-love.  Otherwise known as “smelf love.”  Eh, works for me.

The Loh Down on Science is produced by LDOS Media Lab, with 89.3 KPCC Pasadena, California. And made possible by the generous support of the Gordon and Betty Moore Foundation.

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