Department of Plant Sciences, University of Arizona, 85721, Tucson, AZ, USA.
Theor Appl Genet. 1995 Jul;91(2):200-5. doi: 10.1007/BF00220878.
The natural variation of many traits is controlled by multiple genes, individually referred to as quantitative trait loci (QTL), that interact with the environment to determine the ultimate phenotype of any individual. A QTL has yet to be described molecularly, in part because strategies to systematically identify them are underdeveloped and because the subtle nature of QTLs prevents the application of standard methods of gene identification. Therefore, it will be necessary to develop a systematic approach(es) for the identification of QTLs based upon the numerous positional data now being accumulated through molecular marker analyses. We have characterized a QTL by the following three-step approach: (1) identification of a QTL in complex populations, (2) isolation and genetic mapping of this QTL in near-isogenic lines, and (3) identification of a candidate gene using map position and physiological criteria. Using this approach we have characterized a plant height QTL in maize that maps to chromosome 9 near the centromere. Both map position and physiological criteria suggest the gibberillin biosynthesis gene dwarf3 as a candidate gene for this QTL.
许多性状的自然变异受多个基因控制，这些基因分别被称为数量性状位点（QTL），它们与环境相互作用，决定个体的最终表型。尚未从分子水平上描述 QTL，部分原因是系统鉴定它们的策略尚未开发，部分原因是 QTL 的细微性质阻止了应用标准的基因鉴定方法。因此，有必要根据目前通过分子标记分析积累的大量定位数据，开发一种基于数量性状位点的系统鉴定方法。我们通过以下三步法对 QTL 进行了特征描述：(1) 在复杂群体中鉴定 QTL，(2) 在近等基因系中分离和遗传作图，以及 (3) 使用图谱位置和生理标准鉴定候选基因。我们使用这种方法鉴定了玉米中一个位于 9 号染色体着丝粒附近的株高 QTL。图谱位置和生理标准都表明，赤霉素生物合成基因 dwarf3 是该 QTL 的候选基因。
