On the use of kernel machines for Mendelian randomization

Quantitative Biology
Weiming Zhang, Debashis Ghosh

Abstract

Properly adjusting for unmeasured confounders is critical for health studies in order to achieve valid testing and estimation of the exposure's causal effect on outcomes. The instrumental variable (IV) method has long been used in econometrics to estimate causal effects while accommodating the effect of unmeasured confounders. Mendelian randomization (MR), which uses genetic variants as the instrumental variables, is an application of the instrumental variable method to biomedical research fields, and has become popular in recent years. One often-used estimator of causal effects for instrumental variables and Mendelian randomization is the two-stage least square estimator (TSLS). The validity of TSLS relies on the accurate prediction of exposure based on IVs in its first stage. In this note, we propose to model the link between exposure and genetic IVs using the least-squares kernel machine (LSKM). Some simulation studies are used to evaluate the feasibility of LSKM in TSLS setting. Our results show that LSKM based on genotype score or genotype can be used effectively in TSLS. It may provide higher power when the association between exposure and genetic IVs is nonlinear.

References

Apr 13, 2004·International Journal of Epidemiology·M B Katan
Feb 5, 2008·European Neuropsychopharmacology : the Journal of the European College of Neuropsychopharmacology·Thomas HillemacherMichael Linnebank
Feb 7, 2008·American Journal of Human Genetics·Lydia Coulter KweeMichael P Epstein
Mar 25, 2011·Statistics in Medicine·Stephen Burgess, Simon G Thompson
Jul 9, 2011·American Journal of Human Genetics·Michael C WuXihong Lin
Feb 15, 2012·Advances in Nutrition·Krista S CriderLynn B Bailey
Jun 16, 2012·Biostatistics·Seunggeun LeeXihong Lin
May 21, 2013·American Journal of Human Genetics·Iuliana Ionita-LazaXihong Lin
Jun 19, 2013·American Journal of Human Genetics·Seunggeun LeeXihong Lin
Aug 13, 2015·Clinical Epigenetics·Marieke I Bouwland-BothRégine P M Steegers-Theunissen
Sep 24, 2015·Journal of the American Statistical Association·Wei LinHongzhe Li
Dec 3, 2015·Genetic Epidemiology·Fan WangRui Feng
Jan 7, 2017·Nature Reviews. Endocrinology·Tim Geach

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Citations

Mar 20, 2021·Statistics in Biosciences·Weiming Zhang, Debashis Ghosh

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