Genetic Properties of the Maize Nested Association Mapping Population
Genetic Properties of the Maize Nested Association Mapping Population
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DOI：
10.1126/science.1174320
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发表时间：
2009-08-07
期刊：
影响因子：
56.9
通讯作者：
Buckler, Edward S.
中科院分区：
文献类型：
--
作者：
McMullen, Michael D.;Kresovich, Stephen;Buckler, Edward S.
玉米遗传多样性已被用来理解表型变异的分子基础，并用于提高农业效率和可持续性。我们将25个不同的玉米自交系与B73参考系杂交，共捕获了13.6万个重组事件。重组频率在家系间存在变异，受局部(顺式)遗传变异的影响。我们发现了许多微小的单基因座效应，但很少有两个基因座连锁不平衡或分离扭曲的证据，这表明具有大效应和上位性交互作用的基因对适合度的作用有限。我们在着丝粒周围区域观察到了过量的剩余杂合性，这表明在这些区域，由于重组频率降低，自交系的选择效率较低。这意味着着丝粒周围区域对杂种优势的贡献可能不成比例。
Maize genetic diversity has been used to understand the molecular basis of phenotypic variation and to improve agricultural efficiency and sustainability. We crossed 25 diverse inbred maize lines to the B73 reference line, capturing a total of 136,000 recombination events. Variation for recombination frequencies was observed among families, influenced by local (cis) genetic variation. We identified evidence for numerous minor single-locus effects but little two-locus linkage disequilibrium or segregation distortion, which indicated a limited role for genes with large effects and epistatic interactions on fitness. We observed excess residual heterozygosity in pericentromeric regions, which suggested that selection in inbred lines has been less efficient in these regions because of reduced recombination frequency. This implies that pericentromeric regions may contribute disproportionally to heterosis.