Alessandro Marcon, PhD Unit of Epidemiology & Medical Statistics Department of Diagnostics and Public Health University of Verona Strada Le Grazie 8, 37134 Verona, Italy tel. +39 045 8027668
Avviso di SEMINARIO
Lunedì 12 ottobre 2015 ore 11.00-11.45
Aula Igiene & Statistica
(Istituti Biologici 2, blocco B, secondo piano)
Dr. Cosetta Minelli
Senior Lecturer in Medical Statistics, National Heart and Lung Institute, Imperial College London
Mendelian randomization:
The use of genes as instruments to strengthen causal inference in epidemiology
Mendelian randomization is an approach that uses genes as instrumental variables to derive unconfounded estimates of the effects of risk factors (e.g. biomarkers) on disease traits, and is therefore increasingly being used in epidemiology to distinguish causal from spurious associations. Since genes are randomly allocated at conception, genetic effects on a biomarker cannot be affected by classical confounding (e.g. lifestyle factors) or reverse causation (e.g. biomarker level being influenced by the presence of disease). Demonstration that a genetic variant known to modify the biomarker also modifies the disease trait represents indirect evidence of a causal biomarker-disease association. The validity of Mendelian Randomization, however, is based on instrumental variable assumptions, the most important being absence of pleiotropy. This talk will describe the approach, discuss ways to assess pleiotropy, highlight opportunities and challenges offered by available genome-wide data, and discuss its extension to the field of epigenetics (two-step epigenetic Mendelian randomization).