Kruglyak L, Lander E S
Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA.
Genetics. 1995 Mar;139(3):1421-8. doi: 10.1093/genetics/139.3.1421.
Genetic mapping of quantitative trait loci (QTLs) is performed typically by using a parametric approach, based on the assumption that the phenotype follows a normal distribution. Many traits of interest, however, are not normally distributed. In this paper, we present a nonparametric approach to QTL mapping applicable to any phenotypic distribution. The method is based on a statistic ZW, which generalizes the nonparametric Wilcoxon rank-sum test to the situation of whole-genome search by interval mapping. We determine the appropriate significance level for the statistic ZW, by showing that its asymptotic null distribution follows an Ornstein-Uhlenbeck process. These results provide a robust, distribution-free method for mapping QTLs.
数量性状基因座（QTL）的遗传定位通常采用参数方法，该方法基于表型呈正态分布的假设。然而，许多感兴趣的性状并不呈正态分布。在本文中，我们提出了一种适用于任何表型分布的QTL定位非参数方法。该方法基于统计量ZW，它将非参数Wilcoxon秩和检验推广到通过区间定位进行全基因组搜索的情况。我们通过证明其渐近零分布遵循奥恩斯坦-乌伦贝克过程来确定统计量ZW的合适显著性水平。这些结果为QTL定位提供了一种稳健的、与分布无关的方法。
