Sunday, April 10, 2016

Studies of Domesticated Wheat Genome Reveal Information About Evolutionary Past

Grain and high carbohydrate diets have recieved a bad reputation today for being lacking in nutritional content.  Instead, many grain diets, pasta grains in particular, are regarded as 'empty calories'.  Recently, scientists have attempted to explain the lack of nutritional content in our grains.  A study by Romina Beleggia, Roberto Papa, et al.,  published in the journal of Molecular Biology and Evolution (Oxford University Press), examined study populations of wheat for metabolic content and population genomics.
Three populations were studied to identify two evolutionary changes between each stage.  These were representative of wild emmer, which was domesticated to the emmer grain.  And durum, which came about from emmer.  The domestication of this grain showed a trend of increaing yield by mass.  However, metabolic analyses show that the first domestation of wild type to emmer resulted in a lower production of unsaturated fats.  The change from emmer to durum was found to alter the protien content of the grain.  Co-author Roberto Papa is cited saying that, "not necessarily all of the metabolic variations that occured during domestication have proceeded towards an amelioration of the nutritional quality, probably because yield-related traits were given priority".
The methods of assessment for this study are interesting as they are very large in scale.   The population genomics survey that was performed is a wide-range assesment of the genetic diversity within the selected populations.  The test measures the frequency and variability of selected alleles to give a quantitative measurement of genatic divergence.  To view the free article, click here.

1 comment:

  1. Nathan,

    Thanks for sharing, this was some interesting information. It's sad that not just in modern times, but over the past 10,000 or so years when agriculture rose in popularity and efficiency, we have maintained a consistent quantity over quality method of production. This gives me hope that one day, we will produce genetically-modified wheat containing high levels of nutrition, and lacking so called 'empty calories'!