The gender of a person can now apparently be 'smelled' by human beings.

Wen Zhou of the Chinese Academy of Sciences said that the findings show that the nose can sniff out gender from body secretions even when we don't think we smell anything on the conscious level.
The results provide the first direct evidence that the two human steroids communicate opposite gender information that is differentially effective to the two sex groups based on their sexual orientation.
The findings have been published in the Cell Press journal Current Biology.
Source-ANI