Mendelian randomization (MR) is a method of studying the causal effects of modifiable
exposures (ie, potential risk factors) on health, social, and economic outcomes using genetic …

Randomized controlled trials and Mendelian randomization studies are two study designs
that provide randomized evidence in human biological and medical research. Both exploit …

Estimates from Mendelian randomization studies of unrelated individuals can be biased due
to uncontrolled confounding from familial effects. Here we describe methods for within-family …

Background Genetic influences are ubiquitous as virtually all phenotypes and most
exposures typically classified as environmental have been found to be heritable. A …

The set of methods discussed in this collection has emerged from the convergence of two
scientific fields—genetics and causal inference. In this introduction, we discuss relevant …

In this review, we discuss how samples comprising monozygotic and dizygotic twin pairs can
be used for the purpose of strengthening causal inference by controlling for shared …

Much research effort is invested in attempting to determine causal influences on disease
onset and progression to inform prevention and treatment efforts. However, this is often …

Estimation of direct and indirect (ie parental and/or sibling) genetic effects on phenotypes is
becoming increasingly important. We compare several multivariate methods that utilize …

Children with obesity typically have larger left ventricular heart dimensions during
adulthood. However, whether this is due to a persistent effect of adiposity extending into …

Identifying early causal factors leading to the development of poor mental health and
behavioral outcomes is essential to design efficient preventive interventions. The substantial …