Abstract:
A genome-wide association study (GWAS) was performed in six environments to identify major or consistent alleles responsible for wheat yield traits in Australia and North China where rainfed farming system is adopted. A panel of 228 spring wheat varieties were genotyped by double digest restriction-site associated DNA genotyping-by-sequencing. A total of 223 significant marker-trait association (MTAs) and 46 candidate genes for large- or consistent-effect MTAs were identified. The results were compared with previous studies based on a mini-review of 23 GWAS analyses on wheat yield. A phenomenon seldom reported in previous studies was that MTAs responsible for the trait tended to cluster together at certain chromosome segments, and many candidate genes were in the form of gene clusters. Although linkage disequilibrium (LD) might contribute to the co-segregation of the regions, it also suggested that marker-assisted selection (MAS) or transgenic method targeting a single gene might not be as effective as MAS targeting a larger genomic region where all the genes or gene clusters underlying play important roles.
摘要:
在六个环境中进行了全基因组关联研究(GWAS),以确定澳大利亚和华北地区采用雨养农业系统的小麦产量性状的主要或一致等位基因。通过双消化限制性位点相关的DNA基因分型测序,对228个春小麦品种进行了基因分型。总共鉴定了223个显著的标记-性状关联(MTA)和46个大效应或一致效应MTA的候选基因。基于对23个GWAS小麦产量分析的小型综述,将结果与以前的研究进行了比较。以前的研究中很少报道的现象是,负责该性状的MTA倾向于在某些染色体片段上聚集在一起,许多候选基因以基因簇的形式存在。尽管连锁不平衡(LD)可能导致区域的共分离,它还表明,标记辅助选择(MAS)或针对单个基因的转基因方法可能不如MAS针对更大的基因组区域有效,在该区域中,所有潜在的基因或基因簇都起着重要作用。