Article Figures & Data
Figures
- Fig. 1
A directed acyclic graph depicting how the instrumental variables approach is used in Mendelian randomization. Specifically, Z is the genotype, X is a nutritional exposure, Y is cancer outcome, and C, which is associated with both X and Y, is a potential confounder of an observed association between X and Y. A key assumption underlying the use of instrumental variables in the Mendelian randomization setting is that the association between genotype (Z) and cancer (Y) exists only because the genotype is associated with the nutritional exposure (X); that is, Z is independent of outcome Y given X. This is indicated by the dotted line from Z to Y.
- Fig. 2
A directed acyclic graph depicting how the LCT gene can be used as a proxy (instrumental variable) for dairy product intake in a Mendelian randomization study of prostate cancer.
- Fig. 3
A directed acyclic graph depicting how the HFE gene can be used as a proxy (instrumental variable) for serum ferritin in a Mendelian randomization study of cancer.
Tables
- Table 1
Summary case-control data for sample size calculations
Marker genotype Total aa aA AA Cases r0 r1 r2 R Controls s0 s1 s2 S Total counts n0 n1 n2 N
Volume 2, Issue 2
Jump to section
- Article
- Abstract
- Nutrition and Cancer—the Problem
- Why the Uncertainty in Nutrition and Cancer?
- The Mendelian Randomization Strategy
- How Does Mendelian Randomization Deal with Potential Bias in Observational Epidemiologic Studies?
- How Do Genes Give Us Information on Nutritional Exposure?
- Complexities of the Mendelian Randomization Strategy
- Statistical Power and Sample Size
- What Mendelian Randomization Is Not
- Nutrition-Gene Interactions
- Conclusion
- Disclosure of Potential Conflicts of Interest
- Appendix 1. Sample Sizes for Mendelian Randomization Case-Control Studies
- Footnotes
- References
- Figures & Data
- Info & Metrics