Genome-wide association studies (GWAS) have identified thousands of genetic variants associated with complex traits. Many complex traits are found to have shared genetic etiology. Genetic covariance is defined as the underlying covariance of genetic values and can be used to measure the shared genetic architecture. The data of two outcomes may be collected from the same group or different groups of individuals and the outcomes can be of different types or collected based on different study designs. This paper proposes a unified approach to robust estimation and inference for genetic covariance of general outcomes that may be associated with genetic variants nonlinearly. We provide the asymptotic properties of the proposed estimator and show that our proposal is robust under certain model mis-specification. Our method under linear working models provides robust inference for the narrow-sense genetic covariance, even when both linear models are mis-specified. Various numerical experiments are performed to support the theoretical results. Our method is applied to an outbred mice GWAS data set to study the overlapping genetic effects between the behavioral and physiological phenotypes. The real data results demonstrate the robustness of the proposed method and reveal interesting genetic covariance among different mice developmental traits.
翻译:全基因组协会研究(GWAS)已查明了与复杂特性有关的数千种基因变异,发现许多复杂特性具有共同的遗传病理。遗传共变被定义为遗传价值的基本共变,可用于测量共有的基因结构。两种结果的数据可以从同一群体或不同的个人群体收集,结果可以分为不同类型或根据不同的研究设计收集。本文件建议采取统一办法,对可能与基因变异非线性相关的一般结果的遗传共变进行稳健估计和推断。我们提供了拟议估计器的无症状特性,并表明我们的提议在某些模型错误区分下是稳健的。我们线性工作模型下的方法为狭隘的遗传遗传变异提供了有力的推论,即使两个线性模型都有错误的描述。为了支持理论结果,进行了各种数字实验。我们的方法适用于一个外生小鼠GWAS数据集,用于研究行为和生理变种类型之间重叠的遗传影响。真实数据结果显示了拟议遗传变异的遗传方法的稳健性。