The Older Australian Twins Study, led by Perminder Sachdev of the Centre for Healthy Brain Ageing at the University of New South Wales, has been following TRA twins (65 years old and older) for nearly 15 years and has made a substantial contribution to understanding brain ageing.
Over this perior of time 727 participants have undergone over 1600 assessments of memory and thinking, provided moe than 1400 blood samples and 1600 assessments of memort and thinking, provided more than 1400 blood samples and undergone over 950 MRI scans. This has been a large effort by the team and a gererous contribtuion of study participants in time and sharing of their life experiences.
Brain ageing and brain diseases are determined by multiple genetic factors that interact with environmental influences. Since identical twins share 100 percent of their genes, whereas non-identical twins share half their genetic information, detailed comparisons of these two groups has the potential to discover new genes involved in cognitive decline or resilience.
The OATS team aims to find out what influences memory and thinking as we age. It investigates environmental influences such as lifetime physical and mental activity, socioeconomic environment and nutrition. It also investigates how biological factors such as hypertension and antioxidant levels, interact with genes to influence brain ageing.
Since, over time, the expression of genes varies depending on different influences in the environment, by studying twins, OATS aims to determine which influences on the ageing process are genetic, which are environmental, and how the two interact.
In 2015 a new OATS sub-study was established to investigate the deposition of amyloid plaques in the brain using positron emission tomography (PET) scans.
Using data from 207 PET scans, the OATS team have identified that there is a significant genetic component to the presence of amyloid plaques. Research is still ongoing to identify any potentially modifiable environmental factors that may be contributing to the development of the plaques. Amyloid plaques are thought to predict memory decline with age. We are using our data to establish how amyloid plaques relate to performance in memory and thinking ability.
(Updated March 2021)