RATSS - A twin study of autism and ADHD

The Roots of Autism and ADHD Twin Study in Sweden (RATSS) explores the causes of autism and ADHD in monozygotic and dizygotic (identical and nonidentical) twin pairs with and without neurodevelopmental disorders.

Biological mechanisms behind autism and ADHD

Research shows that both autism and ADHD have mainly biological causes with strong genetic components. Recently published studies have shown that environmental factors also play a major part. The exact mechanisms or processes that cause the conditions are yet to be determined. Neither biological diagnostic tests nor effective treatments targeting the causes of the conditions are currently available.

The purpose of the RATSS project is to carry out basic clinical research in order to increase knowledge on what causes autism and ADHD. The project aims to contribute directly in finding new diagnostic alternatives, and to the development of psychological and medical treatments and prevention of negative outcomes.

Twins can provide new knowledge

RATSS focuses on twin pairs with autism or ADHD, in particular those where one twin in a pair has a diagnosis and the other one does not. Monozygotic twins are especially instructive, since they are genetically very similar. Differences in for example behavior, neurobiology, and genetics within a monozygotic twin pair where only one twin is autistic can be highly relevant to be able to understand the underlying causes, and to develop diagnostic tools and new treatments. In RATSS, twin pairs where one or both twins have autism or ADHD, twin pairs where one or both have another neurodevelopmental condition, and pairs where none of the twins have a diagnosis participate.

To date, over 400 twins have participated in RATSS. While new twins are being recruited, we work on analyzing the data that previous participants have contributed, and with presenting our results at conferences, in scientific journals, and in the media. 

Collaborative effort lead by Karolinska Institutet

The research project is carried out at the Center of Neurodevelopmental Disorders at Karolinska Institutet (KIND), and is managed by Professor Sven Bölte. A number of other departments at Karolinska Institutet, the Swedish Twin Registry, and several international partners are also involved in the study. RATSS is a part of a wider European project called EU-AIMS and AIMS-2 Trials, and of the European collaboration CANDY-multiplex.

Contact person RATSS

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Karl Lundin Remnélius

Projektkoordinator, doktorand
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