For many decades, linkage analysis has been well-established and shown to be an effective tool for studying the complex quantitative traits. Despite of its great successes, this approach has great weakness because it only captures limited allelic diversity existing in two parental lines and also limited in low genomic resolution (Borevitz and Nordborg 2003). To address this issue, GWAS utilizing diverse germplasm collections and recombination events that have been accumulated during the evolution and domestication has been proposed (Zhu et al. 2008). Without the involvements of costs and time for developing mapping populations, GWAS can investigate a set of genetically unstructured genotypes and generate more precise QTL positions if a sufficient
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(2014) conducted GWAS of 282 soybean breeding lines for resistance to SCN HG Type 0 using the USLP 1.0 SNP arrays (Hyten et al. 2010). The authors detected a significant association between markers and the known gene regions but no novel regions were detected. Han et al. (2015) identified 19 association signals significantly related to resistance to SCN HG Types 0 (race 3) and 1.2.3.5.7 (race 4) as well as over 130 new sources of SCN resistance. Among the significant signals, eight were associated with two major QTL, rhg1 and Rhg4. The remaining signals overlapped with other known or new QTL regions. Vuong et al. (2015) analyzed 553 exotic soybean germplasm with over 45,000 SNP markers. The GWAS identified 14 genomic loci and SNPs significantly associated with resistance to SCN HG Type 0. From the study, two major QTL, rhg1 and Rhg4, and also a novel QTL on Chr. 10 (Vuong et al. 2010) were also confirmed. Information on candidate genes and annotation, resistance gene analog (RGA), and transcription factors were also …show more content…
Through GET, DNA can be altered in a very precise manner, often a single base (Huang et al. 2016). For targeted genome editing, two sequence-specific nucleases, zinc finger nucleases (ZFN) and transcription activator-like effector nucleases (TALEN), have been initially proposed to cut in the double-strand DNA in eukaryotic organisms (Ainley et al. 2013). More recently, clustered regular interspaced short palindromic repeats/CRISPR-associated nucleases (CRISPR/Cas) based on the bacterial and archaeal clustered regularly interspaced short palindromic repeats (CRISPR) adaptive immune system has become out as a potent and precise tool for genome editing (Cardi 2016; Sun et al. 2015). In principle, GET is based on the “break” in double-strand DNA by sequence-specific nucleases and then “repairs” through two different procedures; the non-homologous end-joining (NHEJ) or homology-directed repair (HDR) (Gaj et al. 2013, Puchta and Fauser 2014, Rinaldo and Ayliffe 2015, Voytas 2013). In soybean, mutations in targeted genes have been reported for unsaturation level of seed fatty acids by TALEN (Haun et al. 2014) and herbicide resistance by CRISPR/Cas9 (Li et al. 2015). Anyway, genome editing approach in soybean has not been associated with important agronomic traits (Curtin et al. 2011, Jacobs et al.
(2014) conducted GWAS of 282 soybean breeding lines for resistance to SCN HG Type 0 using the USLP 1.0 SNP arrays (Hyten et al. 2010). The authors detected a significant association between markers and the known gene regions but no novel regions were detected. Han et al. (2015) identified 19 association signals significantly related to resistance to SCN HG Types 0 (race 3) and 1.2.3.5.7 (race 4) as well as over 130 new sources of SCN resistance. Among the significant signals, eight were associated with two major QTL, rhg1 and Rhg4. The remaining signals overlapped with other known or new QTL regions. Vuong et al. (2015) analyzed 553 exotic soybean germplasm with over 45,000 SNP markers. The GWAS identified 14 genomic loci and SNPs significantly associated with resistance to SCN HG Type 0. From the study, two major QTL, rhg1 and Rhg4, and also a novel QTL on Chr. 10 (Vuong et al. 2010) were also confirmed. Information on candidate genes and annotation, resistance gene analog (RGA), and transcription factors were also …show more content…
Through GET, DNA can be altered in a very precise manner, often a single base (Huang et al. 2016). For targeted genome editing, two sequence-specific nucleases, zinc finger nucleases (ZFN) and transcription activator-like effector nucleases (TALEN), have been initially proposed to cut in the double-strand DNA in eukaryotic organisms (Ainley et al. 2013). More recently, clustered regular interspaced short palindromic repeats/CRISPR-associated nucleases (CRISPR/Cas) based on the bacterial and archaeal clustered regularly interspaced short palindromic repeats (CRISPR) adaptive immune system has become out as a potent and precise tool for genome editing (Cardi 2016; Sun et al. 2015). In principle, GET is based on the “break” in double-strand DNA by sequence-specific nucleases and then “repairs” through two different procedures; the non-homologous end-joining (NHEJ) or homology-directed repair (HDR) (Gaj et al. 2013, Puchta and Fauser 2014, Rinaldo and Ayliffe 2015, Voytas 2013). In soybean, mutations in targeted genes have been reported for unsaturation level of seed fatty acids by TALEN (Haun et al. 2014) and herbicide resistance by CRISPR/Cas9 (Li et al. 2015). Anyway, genome editing approach in soybean has not been associated with important agronomic traits (Curtin et al. 2011, Jacobs et al.