Wang Ronghuan, Yu Yongtao, Zhao Jiuran, Shi Yunsu, Song Yanchun, Wang Tianyu, Li Yu
Institute of Crop Science, Chinese Academy of Agricultural Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI), 100081 Beijing, People's Republic of China.
Theor Appl Genet. 2008 Nov;117(7):1141-53. doi: 10.1007/s00122-008-0852-x. Epub 2008 Aug 12.
Understanding genetic diversity, population structure, and the level and distribution of linkage disequilibrium (LD) in target populations are of great importance and the prerequisite for association mapping. In the present study, 145 genome-wide SSR markers were used to assess the genetic diversity, population structure, and LD of a set of 95 maize inbred lines which represented the Chinese maize inbred lines. Results showed that the population included a diverse genetic variation. A model-based population structure analysis subdivided the inbred lines into four subgroups that correspond to the four major empirical germplasm origins in China, i.e., Lancaster, Reid, Tangsipingtou and P. Among all of the inbred lines, 65.3% were assigned into the corresponding subgroups; others were assigned into a "mixed" subgroup. LD was significant at a 0.01 level between 63.89% of the SSR pairs in the entire sample and with a range of 18.75-40.28% in the subgroups. Among factors influencing LD, linkage was the major cause for LD of SSR loci. The results suggested that the population may be used in the detection of genome-wide SSR marker-phenotype association.
了解目标群体的遗传多样性、群体结构以及连锁不平衡（LD）的水平和分布非常重要，是关联作图的前提条件。在本研究中，使用145个全基因组SSR标记评估了一组代表中国玉米自交系的95个玉米自交系的遗传多样性、群体结构和LD。结果表明，该群体包含多样的遗传变异。基于模型的群体结构分析将自交系细分为四个亚群，分别对应中国四个主要的经验种质来源，即兰卡斯特、瑞德、塘四平头和P群。在所有自交系中，65.3%被归入相应亚群；其他的被归入“混合”亚群。在整个样本中，63.89%的SSR对之间的LD在0.01水平上显著，在各亚群中的范围为18.75 - 40.28%。在影响LD的因素中，连锁是SSR位点LD的主要原因。结果表明，该群体可用于全基因组SSR标记 - 表型关联检测。
