Cardiovasc Prev Pharmacother.  2020 Jan;2(1):24-30. 10.36011/cpp.2020.2.e3.

Basic Concepts of a Mendelian Randomization Approach

• Go TH
• Kang DR

• KMID: 2536970
• DOI: http://doi.org/10.36011/cpp.2020.2.e3

Abstract

The Mendelian Randomization (MR) approach is a method that enables causal inference in observational studies. There are 3 assumptions that must be satisfied to obtain suitable results: 1) The genetic variant is strongly associated with the exposure, 2) The genetic variant is independent of the outcome, given the exposure and all confounders (measured and unmeasured) of the exposure-outcome association, 3) The genetic variant is independent of factors (measured and unmeasured) that confound the exposure-outcome relationship. This analysis has been used increasingly since 2011, but many researchers still do not know how to perform MR. Here, we introduce the basic concepts, assumptions, and methods of MR analysis to enable better understanding of this approach.

Keyword

Causality; Epidemiologic studies; Genetic association studies; Mendelian Randomization analysis; Observational study

Figure

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  Figure 1. Causal diagram for a Mendelian randomization study.

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