Pork May Order Peak Odor

People have two genes, or most people, that detect a steroidal pheromone called androstenone. This is found in male mammals, specifically pigs. In most developed countries though, pigs are chemically castrated so that there is less androstenone in the meat. A study with 23 volunteers were screened to test their ability to pick of the smell of androstenone where those that had two copies of the gen could easily detect the smell verses the volunteers that had only one copy of the gene.

 http://www.scientificamerican.com/podcast/episode.cfm?id=pork-order-may-peak-odor-12-05-03