Violation of the Constant Genetic Effect Assumption Can Result in Biased Estimates for Non-Linear Mendelian Randomization.

ABSTRACT:

Introduction

Non-linear Mendelian randomization is an extension of conventional Mendelian randomization that performs separate instrumental variable analyses in strata of the study population with different average levels of the exposure. The approach estimates a localized average causal effect function, representing the average causal effect of the exposure on the outcome at different levels of the exposure. The commonly used residual method for dividing the population into strata works under the assumption that the effect of the genetic instrument on the exposure is linear and constant in the study population. However, this assumption may not hold in practice.

Methods

We use the recently developed doubly ranked method to re-analyse various datasets previously analysed usin

SUBMITTER: Burgess S 

PROVIDER: S-EPMC10614256 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature