Wen Yongxian, Wu Weiren
Key Laboratory of Education Ministry for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture & Forestry University, Fuzhou, Fujian, China; School of Computer and Information Science, Fujian Agriculture & Forestry University, Fuzhou, Fujian, China.
Key Laboratory of Education Ministry for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture & Forestry University, Fuzhou, Fujian, China.
PLoS One. 2014 Mar 27;9(3):e92989. doi: 10.1371/journal.pone.0092989. eCollection 2014.
Mapping of imprinted quantitative trait loci (iQTLs) is helpful for understanding the effects of genomic imprinting on complex traits in animals and plants. At present, the experimental designs and corresponding statistical methods having been proposed for iQTL mapping are all based on temporary populations including F2 and BC1, which can be used only once and suffer some other shortcomings respectively. In this paper, we propose a framework for iQTL mapping, including methods of interval mapping (IM) and composite interval mapping (CIM) based on conventional low-density genetic maps and point mapping (PM) and composite point mapping (CPM) based on ultrahigh-density genetic maps, using an immortalized F2 (imF2) population generated by random crosses between recombinant inbred lines or doubled haploid lines. We demonstrate by simulations that imF2 populations are very desirable and the proposed statistical methods (especially CIM and CPM) are very powerful for iQTL mapping, with which the imprinting effects as well as the additive and dominance effects of iQTLs can be unbiasedly estimated.
印记数量性状位点（iQTL）的定位有助于理解基因组印记对动植物复杂性状的影响。目前，已提出的用于iQTL定位的实验设计和相应统计方法均基于包括F2和BC1在内的临时群体，这些群体只能使用一次且分别存在一些其他缺点。在本文中，我们提出了一个iQTL定位框架，包括基于传统低密度遗传图谱的区间定位（IM）和复合区间定位（CIM）方法，以及基于超高密度遗传图谱的点定位（PM）和复合点定位（CPM）方法，使用由重组自交系或双单倍体系随机杂交产生的永生化F2（imF2）群体。我们通过模拟证明，imF2群体非常理想，所提出的统计方法（尤其是CIM和CPM）对iQTL定位非常有效，利用这些方法可以无偏估计iQTL的印记效应以及加性和显性效应。
