Impacts Of Genome Diversity and Structural Variation In Soybean

Genome-wide structural variation, such as large deletions and duplications, are hypothesized to drive important phenotypic variation. Recent advances involving array hybridization and targeted resequencing now allow for the genome-wide assessment of structural and gene content variation within a species. We have used these methods to assess natural and induced genome variation in soybean cultivars and mutant lines. High rates of natural structural variation have been observed within gene-rich regions that harbor clustered multi-gene families, particularly the Nucleotide Binding (NB) and Receptor-Like Protein (RLP) classes, both of which are important for plant biotic defense responses. The co-localization of structural variants with elements of the plant defense response signal transduction pathways provides insight into the mechanisms and frequencies of soybean resistance gene evolution. Emerging technologies may soon allow for the establishment of genetic stocks with targeted structural variants that can address new hypotheses about the relationship between structural variation and disease gene evolution in soybean.