TEDS turns 20

The Twins Early Development Study (TEDS) based at the Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London, has celebrated 20 years of ground-breaking scientific discovery at an event that explored the genesis of TEDS, its key achievements to date and its future direction.  

Thanks to 20,700 UK twins, scientists using cutting-edge research in psychology, psychiatry and genetics have been able to unpick the complex relationship between nature and nurture, transforming the way we think about genetic and environmental influences on diverse areas of behavioural development.

Early collaborators Dr Bonny Oliver and Professor Philip Dale opened the event, describing the birth of TEDS and its humble beginnings, before introducing Thalia Eley, Professor of Developmental Behavioural Genetics and Deputy Director of TEDS, who talked about the science and the stories of TEDS.

Robert Plomin, Professor of Behavioural Genetics and Director of TEDS, acknowledged the study's major impact in 'changing the zeitgeist in terms of nature and nurture, moving the whole discussion closer to a balanced view.' He thanked members of the 'TEDS family' for their contributions to the success of the project, and recognised the crucial backing provided by the Medical Research Council's Social, Genetic & Developmental Psychiatry (SGDP) Centre, the project's home at King's. He acknowledged SGDP directors past and present, including founder Professor Sir Michael Rutter, Professor Peter McGuffin and current director Professor Francesca Happé, for their support.

We spoke to Professor Eley about the past, present and future of TEDS.

What has been your proudest achievement or defining moment while working on the TEDS project?
My proudest achievement was when Robert asked me to become Deputy Director of TEDS with a view to taking over as Director in 2018. It is such a wonderful project and leaves such a lasting legacy, I was really honoured to be given that role. Another very proud moment was when my first PhD student Dr Alice Gregory, now a Reader at Goldsmiths, completed and was awarded her PhD (in 2004), having used data from the TEDS sample for many of her analyses.

How has the project changed over the years, in terms of its focus or how it's conducted?
The main change has been to shift from asking the parents to tell us about their children, to asking the twins to tell us about themselves as they are now young adults. I used to be told I would know I was old when policemen started looking young. Instead I feel old now that the twins I have worked with since they were toddlers are all young adults building their own independent lives! Another big shift for us has been to move to using the internet for a lot of our assessments. This really makes it practical and in many ways more fun for the twins themselves.

What are you working on now?
I am working with a PhD student called Laurie Hannigan on some analyses in which we are exploring how the twins and their parents saw their relationship during the teenage years – what they saw the same and what they saw differently. The next step will be to look at how that relates to emotional and behavioural symptoms they also reported during that period.

What's next for TEDS?
We just received our fifth programme grant from the MRC in which we will assess all the twins in their early 20s and also do an in-depth assessment on a subset of them, finding out how they are doing as they navigate the first steps of independent adult life. For me personally, a real excitement is that the TEDS twins are beginning to have children themselves. I have been working for a few years now with a design called 'Children of twins', which allows you to disentangle the relative influence of genes versus the environment on transmission of traits within families down through the generations. Having so much data on the TEDS twins from when they were very young will put us in a unique position when it comes to understanding intergenerational transmission. 

- Jon Sutton

I    A video about the study, 'TEDS – The Journey So Far', is available at youtu.be/-LAGbuQnBnQ