Genetic studies provide valuable information to assess if the effect of genetic variants varies by the nongenetic "environmental" variables, what is traditionally defined to be gene-environment interaction (GxE). A common complication is that multiple disease states present with the same set of symptoms, and hence share the clinical diagnosis. Because (a) disease states might have distinct genetic bases; and (b) frequencies of the disease states within the clinical diagnosis vary by the environmental variables, analyses of association with the clinical diagnosis as an outcome variable might result in false positive or false negative findings. We develop estimates for this setting to be able to assess GxE in a case-only study and we compare the case-control and case-only estimates. We report extensive simulation studies that evaluate empirical properties of the estimates and show the application to a study of Alzheimer's disease.

中文翻译：

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病例对照与仅病例的基因与环境相互作用的估计以及常见和错误分类的临床诊断。

遗传研究提供有价值的信息，以评估遗传变异的影响是否因非遗传“环境”变量而异，传统上将其定义为基因与环境的相互作用（GxE）。常见的并发症是多种疾病状态具有相同的症状，因此具有共同的临床诊断。因为（a）疾病状态可能具有不同的遗传基础；（b）临床诊断中疾病状态的频率因环境变量而异，与临床诊断的关联性作为结果变量的分析可能会导致假阳性或假阴性结果。我们针对这种情况制定估计值，以便能够在仅案例研究中评估GxE，并比较案例对照和仅案例估计。