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Published on: January 8, 2020
[Mendelian randomization approach, used for causal inferences]
1Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing 210009, China.
Abstract:
Mendelian randomization (MR) approach is based on the Mendelian genetic law, which is called "Parental alleles that randomly assigned to the offspring" . MR refers to the use of genetic variants to develop causal inferences from observational data, if the variant genotype is associated with the phenotype and the variant genotype associated with the risk of disease of interest through the phenotype. Hence, the genotype can be used as Instrumental Variable (IV) to infer the causal relation between the phenotype and the risk of diseases. In recent years, MR approach is widely used in causal inference between the exposure factors and the risks of disease, along with the rapid development of statistical methods, big datasets of GWAS, epigenetics and the various "omics" techniques. This paper provides an overview of the MR strategies and addresses the related assumptions and implications, with reliability and limitations included.
Insights
Mendelian randomization (MR) uses genetic variants to infer causal links between exposures and diseases. This method leverages random genetic assignment for robust observational data analysis, exploring reliability and limitations.
Area of Science:
- Genetics
- Epidemiology
- Biostatistics
Background:
- The Mendelian randomization (MR) approach utilizes Mendelian's law of random genetic inheritance.
- MR enables causal inference from observational data by employing genetic variants as instrumental variables.
- Its application has surged due to advancements in statistical methods and large-scale omics datasets.
Purpose of the Study:
- To provide a comprehensive overview of Mendelian randomization strategies.
- To discuss the assumptions, implications, reliability, and limitations of the MR approach.
- To highlight the utility of MR in causal inference for disease risk.
Main Methods:
- Utilizing genetic variants as instrumental variables (IV).
- Assessing the association between genotype, phenotype, and disease risk.
- Applying advanced statistical methods to observational data.
Main Results:
- Mendelian randomization offers a robust framework for causal inference.
- The method's reliability is contingent on the validity of its underlying assumptions.
- Understanding limitations is crucial for accurate interpretation of MR findings.
Conclusions:
- Mendelian randomization is a powerful tool for establishing causality in epidemiological research.
- The approach requires careful consideration of assumptions and potential biases.
- Continued methodological development enhances the power and applicability of MR.
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