While gene-environment (GxE) interactions contribute importantly to many different phenotypes, detecting such interactions requires well-powered studies and has proven difficult. To address this, we combine two approaches to improve GxE power: simultaneously evaluating multiple phenotypes and using a two-step analysis approach. Previous work shows that the power to identify a main genetic effect can be improved by simultaneously analyzing multiple related phenotypes. For a univariate phenotype, two-step methods produce higher power for detecting a GxE interaction compared to single step analysis. Therefore, we propose a two-step approach to test for an overall GxE effect for multiple phenotypes.

中文翻译：

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一种两步法来测试基因-环境相互作用对多种表型的整体影响

虽然基因-环境 (GxE) 相互作用对许多不同的表型有重要贡献，但检测此类相互作用需要强有力的研究并且已被证明是困难的。为了解决这个问题，我们结合了两种方法来提高 GxE 功效：同时评估多种表型和使用两步分析方法。以前的工作表明，可以通过同时分析多个相关表型来提高识别主要遗传效应的能力。对于单变量表型，与单步分析相比，两步法可产生更高的检测 GxE 相互作用的能力。因此，我们提出了一种两步法来测试多种表型的整体 GxE 效应。