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Updated: Sep 7, 2025
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An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
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Weak allele versus null allele: which one to select?
Bing Xiao1, Pei Li2, Qingyu Wu3
1Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; College of Resources and Environmental Sciences, China Agricultural University, Beijing 100091, China.
Trends in Genetics : TIG
|June 17, 2022
Summary
Maize and rice domestication involved similar molecular changes. A genome-wide study found that the maize KERNEL ROW NUMBER2 (KRN2) gene and its rice counterpart underwent parallel evolutionary selection, highlighting conserved genetic mechanisms.
Area of Science:
- Genomics
- Plant domestication
- Evolutionary biology
Background:
- Maize and rice, vital cereal crops, were independently domesticated from wild ancestors.
- Understanding the genetic basis of domestication is key to crop improvement.
- Convergent phenotypic evolution in domesticated species may involve conserved molecular mechanisms.
Purpose of the Study:
- To investigate whether conserved molecular changes underlie convergent phenotypic selection during maize and rice domestication.
- To identify specific genes that experienced parallel selection in both species.
Main Methods:
- Genome-wide analysis of maize and rice genomes.
- Comparative genomics to identify orthologous genes.
- Selection signature analysis to detect convergent evolution.
Main Results:
- The study identified genes that experienced convergent selection in both maize and rice.
- Specifically, the maize KERNEL ROW NUMBER2 (KRN2) gene and its rice ortholog showed evidence of parallel selection.
- This suggests conserved molecular pathways were targeted during domestication.
Conclusions:
- Convergent phenotypic selection during maize and rice domestication was driven by conserved molecular changes.
- The KRN2 gene exemplifies how similar genetic mechanisms can be selected during independent domestication events.
- These findings provide insights into the genetic architecture of crop domestication.
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