Date: Thursday 24th January 2019, 3.30 pm in the IT Teaching Suite, Department of Statistics
Speaker: Kevin Sharp, Department of Statistics, University of Oxford
Title: Multiple phenotype models and the genetic basis of brain structure and function
Abstract: Much is unknown about the genetic basis of brain structure and function.
Magnetic Resonance Imaging (MRI) provides a powerful, non-invasive technique for obtaining estimates of relevant quantities such the volumes, and thicknesses of different structures within the brain or the integrity of the connections between them. Recently, we carried out genetic association studies of 3,144 such structural and functional brain imaging phenotypes in the first tranche of 8428 imaged subjects from the UK Biobank . In terms of the number of phenotypes analysed, this is by far the largest study of its kind so far undertaken. In this talk, I will discuss this work together with our ongoing analysis based on twice as many individuals. In particular, I will focus on the utility of multivariate models. Such approaches fit a joint model for the association between a genetic variant and a group of correlated traits and can utilise estimates of genetic correlation to boost power. If time permits, I will also describe a sparse extension of this model which can be more powerful when only a small subset of phenotypes is truly associated.
I will try to provide sufficient background so that no prior knowledge of genetics is required!
 Lloyd T. Elliott, Kevin Sharp, Fidel Alfaro-Almagro, Sinan Shi, Karla Miller, Gwenaëlle Douaud, Jonathan Marchini, Stephen Smith. Genome-wide association studies of brain imaging phenotypes in UK Biobank. Nature volume 562, pages 210–216 (2018).