违反常数遗传效应假设可能导致对非线性孟德尔随机化的偏差估计
1MRC Biostatistics Unit, University of Cambridge, Cambridge, UK.
Human heredity
|August 31, 2023
概括
对比了非线性门德尔随机化方法,揭示了双排列方法可能比遗传效应变化时的残余方法提供更少偏差的因果效应估计. 分析师应该使用这两种方法来获得可靠的维生素D补充发现.
科学领域:
- 流行病学 流行病学
- 遗传流行病学遗传流行病学
- 生物统计学 生物统计学
背景情况:
- 非线性门德尔随机化扩展了传统方法,通过分析不同暴露水平的因果关系.
- 剩余方法假设对暴露的基因影响是恒定的,这可能不适用于现实世界的数据.
- 这种假设的违反可能会导致因果推理研究中的偏见估计.
研究的目的:
- 将双排列方法与非线性门德尔随机化的残余方法进行比较.
- 用遗传评分来评估25-氧维生素D (25[OH]D) 对所有原因死亡率的因果作用.
- 为了评估不同暴露的恒定遗传效应假设的有效性.
主要方法:
- 使用新开发的双排列方法重新分析现有数据集.
- 应用非线性门德尔随机化方法,以25(OH) D.的遗传分数进行应用.
- 进行了分层的仪器变量分析.
主要成果:
- 基因评分25...OH) D显示,在最低分数和最高分数之间,与暴露水平的关联是五倍的差异.
- 剩余方法表明维生素D对维生素D缺乏个体的死亡率有保护作用,但双排列方法没有.
- 发现恒定遗传效应假设对一些,但不是所有暴露更合理.
结论:
- 双排列方法可能会在违反常数遗传效应假设时提供更少偏差的估计.
- 分析师应在非线性门德尔随机化中使用剩余和双排列方法.
- 为了减轻遗传效应的异质性,残留方法可能需要改变暴露.
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