The genetic architecture of maize height.
The genetic architecture of maize height.
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DOI：
10.1534/genetics.113.159152
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发表时间：
2014-04
期刊：
影响因子：
3.3
通讯作者：
Buckler ES
中科院分区：
文献类型：
--
作者：
Peiffer JA;Romay MC;Gore MA;Flint-Garcia SA;Zhang Z;Millard MJ;Gardner CA;McMullen MD;Holland JB;Bradbury PJ;Buckler ES
玉米株高是玉米遗传性最强、最容易测定的性状之一。给定系谱或相关植物中的基因组身份的估计，高度也是准确可预测的。但是，定位解释玉米高度自然变异的等位基因仍然是一个艰巨的挑战。为了应对这一挑战，我们测量了13个环境中超过64，500个地块中生长的植物的株高、穗高、开花时间和节点数。这些地块包含>7300个代表美国最具市场价值的玉米自交系和玉米巢式关联作图（NAM）小组的家系的自交系。进行了数量性状基因座（QTL）的连锁定位、近等基因系（NIL）的精细定位、全基因组关联研究（GWAS）和基因组最佳线性无偏预测（GBLUP）。玉米株高的遗传力在90%以上。NAM家系嵌套QTL的定位揭示了最大的解释高度变异的2.1 ± 0.9%。两个热带等位基因在这个QTL的影响独立验证了精细定位在近等基因组家庭。GWAS发现的几个重要关联与已建立的高度基因座共定位，包括油菜素内酯缺乏的侏儒1，矮植物1和半侏儒2。GBLUP解释了面板中>80%的高度变异，并且在预测精度评估中优于家系嵌套QTL模型的自举聚合。这些结果表明，玉米株高受较强的遗传控制，具有高度的多基因遗传结构。他们还表明，多基因性和效应大小不同的遗传结构的多个模型可以合理地解释玉米高度的群体变异，但它们在预测效力上可能会有所不同。
Height is one of the most heritable and easily measured traits in maize (Zea mays L.). Given a pedigree or estimates of the genomic identity-by-state among related plants, height is also accurately predictable. But, mapping alleles explaining natural variation in maize height remains a formidable challenge. To address this challenge, we measured the plant height, ear height, flowering time, and node counts of plants grown in >64,500 plots across 13 environments. These plots contained >7300 inbreds representing most publically available maize inbreds in the United States and families of the maize Nested Association Mapping (NAM) panel. Joint-linkage mapping of quantitative trait loci (QTL), fine mapping in near isogenic lines (NILs), genome-wide association studies (GWAS), and genomic best linear unbiased prediction (GBLUP) were performed. The heritability of maize height was estimated to be >90%. Mapping NAM family-nested QTL revealed the largest explained 2.1 ± 0.9% of height variation. The effects of two tropical alleles at this QTL were independently validated by fine mapping in NIL families. Several significant associations found by GWAS colocalized with established height loci, including brassinosteroid-deficient dwarf1, dwarf plant1, and semi-dwarf2. GBLUP explained >80% of height variation in the panels and outperformed bootstrap aggregation of family-nested QTL models in evaluations of prediction accuracy. These results revealed maize height was under strong genetic control and had a highly polygenic genetic architecture. They also showed that multiple models of genetic architecture differing in polygenicity and effect sizes can plausibly explain a population’s variation in maize height, but they may vary in predictive efficacy.