Launch of global Alzheimer's study by Cardiff University
3 April 2014 Last updated at 09:59 BST
Scientists from Cardiff University are leading a global project to explore the relationship between genetics and lifestyle in the development of Alzheimer's disease.
The £6m study will involve more than one million people and aims to produce the most comprehensive understanding of the disease's risk to date.
Prof Julie Williams, who is leading the project, spoke to BBC Radio Wales.