title: Mendelian randomization in family data.
abstract: The phrase "mendelian randomization" has become associated with the use of genetic polymorphisms to uncover causal relationships between phenotypic variables. The statistical methods useful in mendelian randomization are known as instrumental variable techniques. We present an approach to instrumental variable estimation that is useful in family data and is robust to the use of weak instruments. We illustrate our method to measure the causal influence of low-density lipoprotein on high-density lipoprotein, body mass index, triglycerides, and systolic blood pressure. We use the Framingham Heart Study data as distributed to participants in the Genetics Analysis Workshop 16.
authors.affiliation: Department of Epidemiology and Biostatistics, MS 72818, Wolstein Building, 2103 Cornell Road, Case Western Reserve University, Cleveland, Ohio 44106, USA. njm18@case.edu.
authors.forename: Nathan J
authors.initials: NJ
authors.lastname: Morris
authors.forename: Courtney
authors.initials: C
authors.lastname: Gray-McGuire
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Stein