The genetic architecture of the maize progenitor, teosinte, and how it was altered during maize domestication

by Qiuyue Chen, Luis Fernando Samayoa, Chin Jian Yang, Peter J. Bradbury, Bode A. Olukolu, Michael A. Neumeyer, Maria Cinta Romay, Qi Sun, Anne Lorant, Edward S. Buckler, Jeffrey Ross-Ibarra, James B. Holland, John F. Doebley

The genetics of domestication has been extensively studied ever since the rediscovery of Mendel’s law of inheritance and much has been learned about the genetic control of trait differences between crops and their ancestors. Here, we ask how domestication has altered genetic architecture by comp aring the genetic architecture of 18 domestication traits in maize and its ancestor teosinte using matched populations. We observed a strongly reduced number of QTL for domestication traits in maize relative to teosinte, which is consistent with the previously reported depletion of additive variance by selection during domestication. We also observed more dominance in maize than teosinte, likely a consequence of selective removal of additive variants. We observed that large effect QTL have low minor allele frequency (MAF) in both maize and teosinte. Regions of the genome that are strongly diff erentiated between teosinte and maize (high FST) explain less quantitative variation in maize than teosinte, suggesting that, in these regions, allelic variants were brought to (or near) fixation during domestication. We also observed that genomic regions of high recombination explain a disproportionately large proportion of heritable variance both before and after domes...

Source: PLoS Genetics - May 13, 2020 Category: Genetics & Stem Cells Authors: Qiuyue Chen Source Type: research