基于性状-标记回归的QTL区间测验方法

摘要

本文提出了两种基于性状-标记回归的QTL区间测验方法，分别称为TMRIT-I和TMRIT-II。前者采用似然比统计量进行显著性测验，与基于最小二乘的简化复合区间定位法（sCIM）等价，但计算上明显简单快捷；后者则采用一种“伪似然比”统计量进行显著性测验，不仅进一步简化计算，而且明显提高统计功效。二者皆可通过排列测验估计显著阈值。给出了一个模拟例子。%Two methods of interval test of quantitative trait loci (QTLs) based on trait-marker regression are proposed, named as TMRIT-I and TMRIT-II, respectively. The former uses likelihood ratio statistic for significance test, equivalent to the method of simplified composite interval mapping (sCIM) based on least squares, but much simpler and quicker in calculation. The latter uses a ‘pseudo-likelihood ratio’ statistic for significance test, not only simplifying calculation further, but also significantly increasing statistical power. For both methods, significance threshold can be estimated by permutation tests. A simulated example is given.