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bioRxiv · 10.1101/2023.03.31.535022

An integrated map of genetic variation from 1,062 wheat genomes

Abstract

The construction of a high-quality wheat genome variation map is important to wheat genetic studies and breeding. In this study, we developed the second-generation whole-genome genetic variation map of wheat (VMap 2.0) by integrating whole-genome sequencing data of 1,062 diverse wheat accessions from 20 species/subspecies. VMap 2.0 contains 195.96 million single nucleotide polymorphisms (SNPs), 2.22 million insertions, and 4.72 million deletions, achieving a high density of variation map in which one variant exists in every 73 base pairs on average. By systematically analyzing the phylogenetic relationships and genetic diversity of tetraploid wheat, hexaploid wheat, and diploid goatgrass (Aegilops tauschii), we found that the genetic diversity of wild emmer wheat was 2.4 times higher than that of common wheat. In contrast, the genetic diversity of diploid goatgrass is 7.8 times higher than the D subgenome of hexaploid wheat. With the high-density genetic variations, VMap 2.0 is anticipated to facilitate high-resolution trait dissection and expedite prediction-based breeding of wheat.

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BibTeXRIS

Bi, A., Xu, D., Kang, L., Guo, Y., Song, X., Zhao, X., Zhang, J., Zhang, Z., Li, Y., Yin, C., Wang, J., Lu, F.. 2023-04-01. An integrated map of genetic variation from 1,062 wheat genomes. https://doi.org/10.1101/2023.03.31.535022

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