Asparagus and the Aftereffects
Study Finds Genetic Reason for the Ability to Smell the Urinary Metabolites of Asparagus
As the asparagus season is starting, the discussion about the origin of the change in smell of the urine after eating asparagus will become more heated.
The discussion in the academic field so far revolved around the question if it was either the ability to produce methanethiol (the strong smelling compound) was inherited in an autosomal dominant manner, or the ability to detect it was a roughly bimodal trait. A group of researchers has taken the challenge to look deeper into the data produced by the company 23andme, who specialises in personal genome analysis. The customers volunteered to answer a survey and also agreed to have their genetic data analysed by the researchers.
According to the publication, the team has identified a locus associated with this trait. This locus lies within a region containing many olfactory receptors and appears to act in a dominant fashion. Both of these facts suggest that the genetic variation in this trait is in the ability to detect the odorant.
Eriksson, N., et al.: Web-Based, Participant-Driven Studies Yield Novel Genetic Associations for Common Traits. PLoS Genetics, 6(6),(2010), doi:10.1371/journal.pgen.1000993