Your Body Doesn't Stink Like Others

You Know this, Your body has a signature odour, just as your fingers have unique prints

Mammals such as mice and humans are known to have unique, genetically determined body odours, called odortypes, which act something like olfactory nametags, helping distinguish to individuals from one another, even pick out a mate.
An individual's odortype is determined in part by genes in a genomic region called the major histocompatibility complex (MHC), which plays a role in the immune system and are found in most vertebrates.

Odourtype information is transmitted through body fluids such as sweat and urine, which contain numerous airborne chemical molecules known as volatile organic compounds (VOCs), many of which give off an odor, as anyone who's been in a gym locker room probably knows.

Meanwhile, the type of food an animal or person eats can influence their body odour; garlic, when consumed in large amounts, is a well-known example.

So researchers looked into the question of whether or not changes in diet could possibly get in the way of one's genetically determined odortype and thus mask aromatic identity.

In behavioral tests, "sensor" mice were trained to use their sense of smell to choose between pairs of test mice that differed in MHC genes, diet or both. Researchers used chemical analyses to examine the array of VOC's in urine of mice having different MHC backgrounds and fed different diets.The results, indicate that genetically determined odortypes persisted regardless of what the mice ate, even though dietary changes did strongly influence the odor profiles of individual mice. Both the sensor mice and chemical analyses could still detect the underlying odortypes.

The findings using this animal model support the proposition that body odours provide a consistent 'odorprint' analogous to a fingerprint or DNA sample.