QLS Featured Seminar Series - Dr. Jonathan Marchini

Brain imaging genetics in the UK Biobank

Jonathan Marchini

Statistics, University of Oxford

Abstract: Brain structure, function and connectivity are known to vary between individuals in the human population. Changes in these features have been identified in many neurological and psychiatric disorders such as Alzheimer's disease, Parkinson's disease, schizophrenia, major depression, autism, bipolar disorder as well as drug addiction. Understanding the genetic basis of these brain traits will have high relevance to neurological, psychiatric, degenerative and developmental disorders.

In 2017 the UK Biobank released high quality brain imaging data on 10,000 subjects. A fully automated processing pipeline has been developed for UK Biobank that produces both processed images as well as image-derived phenotypes (IDPs); this generates thousands of distinct individual measures of brain structure and function. Example IDPs include the volume of specific brain structures, the strength of connectivity between pairs of brain regions and the dispersion of fibers in a given white-matter tract.

UK Biobank has also collected genome-wide genetic data on every participant using a purpose-designed genotyping array. A custom quality control, phasing and imputation pipeline was developed to address the challenges specific to the experimental design, scale, and diversity of the UK Biobank dataset. The genetic data was released to researchers with approved access in July 2017 and consists of ~96 million genetic variants in ~500,000 study participants.

The talk will describe the joint analysis of the genetic and brain imaging datasets available from UK Biobank. This will include a decription of some of the novel methods we have developed to cope with the scale of the genetic and brain imaging data, as well as a description of the main findings of the study so far.