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Love connection

The major histocompatibility complex (MHC) is a set of genes that controls cell-surface molecules, which the body uses to tell self from foreign invaders.

Our bodies exude MHC levels through sweat and body odor, as well as saliva. There are a wide variety of MHC types, but they tend to more closely match in people who are related.

Based on scent and taste, studies suggest we can pick up on MHC levels in other people, and it’s thought that the more you differ in MHC, the stronger the attraction.

Next: Follow your nose