MORE than 1,000 Scots are to have their entire genetic make-up decoded to help explain why some people's brains age better than others.

The DNA analysis will help researchers at Edinburgh University determine the impact that a person's genetic make-up has on their ability to stay sharp in old age.

The participants will come from the Lothian Birth Cohort 1936, a group of individuals from Edinburgh who were born in 1936 and took part in school mental tests as 11-year-olds.

These exam results have been combined with studies of each individual's thinking skills and health over the past decade, forming a major study into how mental ability in youth affects the brain in later life.

As well as regularly resitting the school mental test, the cohort have taken many cognitive tests and medical examinations, including blood and ultrasound checks, brain scans, eye examinations and fitness assessments.

By linking these test results with information about their genetic make-up, scientists hope the study will give new insights into the factors underlying healthy ageing.

Edinburgh University's Roslin Institute and Centre for Cognitive Ageing and Cognitive Epidemiology have received £1m from the Biotechnology and Biological Sciences Research Council to fund the study.

Professor Ian Deary, director of the Centre for Cognitive Ageing and Cognitive Epidemiology, said: "As well as lifestyle factors and health, we think that genetic factors contribute to why some people's brains and thinking skills age better than others. Until now, our genetic testing of the Lothian Birth Cohort 1936 has been patchy. This new award will allow us comprehensively to examine people's genetic status, and will add further value to the rich data provided by these dedicated participants. My Centre is delighted to be working with the Roslin Institute on this large scale and important new part of the project."