标题： 利用DNA标记表征等位基因和复杂单倍型的有效策略 显示英文标题

标题： An efficient strategy to characterize alleles and complex haplotypes using DNA-markers

摘要： 我们考虑这样一个问题：当无法直接获取某个基因组小区域（例如一个基因或基因复合体）的信息时，检测并估计感兴趣性状与该区域中的等位基因或单倍型之间的关联强度。然而，邻近的DNA标记物的值是可以获得的。 我们认为，非可观察的基因组区域的单倍型效应可以通过表示不相交标记-等位基因组群的因素来体现，并且应该这样处理。 基于一个假设的系统发育树的理论论证支持这一总体主张。 所描述的技术允许识别和推断与性状相关的基因组区域内可检测到的单倍型的数量。 所提出的方法使用了结合极大化惩罚参数数量的似然函数版本的穷举组合搜索。 对于适度数量的标记-等位基因，这种程序可以轻松地用标准统计方法实现。 显示英文摘要

摘要： We consider the problem of detecting and estimating the strength of association between a trait of interest and alleles or haplotypes in a small genomic region (e.g. a gene or a gene complex), when no direct information on that region is available but the values of neighbouring DNA-markers are at hand. We argue that the effects of the non-observable haplotypes of the genomic regions can and should be represented by factors representing disjoint groups of marker-alleles. A theoretical argument based on a hypothetical phylogenetic tree supports this general claim. The techniques described allow to identify and to infer the number of detectable haplotypes in the genomic region that are associated with a trait. The methods proposed use an exhaustive combinatorial search coupled with the maximization of a version of the likelihood function penalized for the number of parameters. This procedure can easily be implemented with standard statistical methods for a moderate number of marker-alleles.