The TwinsUK Registry
TwinsUK is the UK’s largest ADULT twin registry with over 15,000 twins (identical and non-identical) aged 18-100. Twins have taken part in valuable health and ageing research since 1992 overseen by the Department of Twin Research.
Who Can Join?
Please do not register with us if you are not a twin. You can take part in our COVID-19 symptom tracking study if you are not a twin, without registering with us. Please find more information about this here.
Any twins, identical or non-identical, who are 18 years of age and older, living in the UK or overseas can join the registry and take part in our research programme.
Twins of different sex can join the registry and receive our updates but please be aware that there is a possibilty that you may not be contacted to take part in our current research programme due to the difficulties in comparing male and female twins in research.
PHONE: +44 (0) 20 7188 5555
ONLINE: Complete a few simple steps to register with us
By supplying your personal details you are agreeing for us to register these details and contact you at regular intervals but please rest assured that no personal details will be supplied to any external organizations or collaborators without your prior consent
What does participation involve?
You can choose to participate in our research in a number of ways:
- All twins are invited for a full-day twin research visit at the Department of Twin Research based at St Thomas’ Hospital in London approximately every four years. The research visit involves a number of tests such as blood tests (including a cholesterol and diabetes check, as well as DNA), bone density, blood pressure, cardiac assessments, simple fitness and sensory tests, eye tests and more. Clinically useful results are posted to participants approximately 4 to 6 weeks after the visit.
- All twins are invited to take part in postal studies.
- All twins are invited to complete questionnaires by post and/or on-line (one or two per year).
- Sub-sets of twins may be invited to participate in research focused on a specific condition/ disease.
FAQ about volunteering
1. Why take part in research?
Why are twins of such great value to health research?
- Our health and how we age is mostly determined by a combination of our unique genetic makeup (nature) and our environment such as lifestyle and life experiences (nurture). The genes of identical twins are 100% the same so comparing them with non-identical twins, who share only 50% of their genes, allows us to separate the genetic and environmental factors, and enables researchers to accurately measure the effects of our environment and life-style on our health.
- Our research using the DNA of twin research volunteers and the data from twin visits and questionnaires has led to a number of important research discoveries and projects:
- We have been able to work out how much our genes influence common traits and diseases. For example, we have discovered that many common diseases of ageing (such as Type 2 diabetes and osteoarthritis) are, for most people, caused more by life-style and life-experience than by genes.
- We have also been able to pinpoint the specific genes that contribute to the development of disease such as type 2 diabetes, melanoma and osteoporosis.
- Our work on healthy ageing and frailty is aiming to identify new ways to predict and prevent frailty so that we can all age as healthily as possible
- Our work on the microbiome (the bacteria that live inside us) is revealing important insights into how our health and immune system are closely linked to the bacteria that live in our guts.
What does the research process look like?
Carrying out a research study takes months, sometimes years of preparation and research, funding applications and ethics approval. The first step is the conception of an original research idea that can be effectively carried out in a research setting and will yield results that have the potential to contribute to our understanding of the body and how it works. To see the whole research process explained in detail, please click here to go to Study Life Cycle page
What are the benefits of participating?
Apart from contributing to important health research that will improve our knowledge of complex disease and how to treat them, taking part in research can also benefit you by allowing you to have a full health MOT at your twin visit. We are able to provide you with clinically useful results for some of the tests.
2. The practicalities of taking part in research
How often are volunteers asked to come for a twin visit?
Currently we are inviting twin volunteers to come for a visit approximately once every four years. This timeline enables us to see most of the twins on our registry, tracking valuable health changes with time. In between twin visits we rely on the data collected in online-postal questionnaires to keep us up to date. If you are a member of TwinsUK and have not been in for a visit for about four years, or would like to join the registry, please call 0207 188 5555 to arrange a visit.
I would like to take part in a study but I cannot come in to the DTR; can I still take part?
Yes, although the twin visit provides very valuable data, our questionnaires also give us an enormous amount of information for use in research. There are also some studies which you can do from home for example, saliva and hair samples can be collected via post as we can extract DNA from these samples for use in research. We may also ask for twins to donate blood through their GP and post the sample to us.
I live abroad; can I still take part in studies?
Yes, you can still make a valuable contribution by taking part by completing our online questionnaires.
Will you cover my expenses?
Travel: Yes, you will be eligible to have some or all of your transport costs covered. Due to being charity-funded we do ask volunteers to book their travel as far in advance as possible and by the cheapest means possible. When you book your visit, the admin team will provide you with more information.
Daily expenses – Regrettably because we are a charity-funded organisation, we are unable to cover work expenses so we rely on the good will of volunteers to kindly donate their valuable time for the benefit of research.
Accommodation – The provision of over-night accommodation close to St Thomas’ depends on where you live. When you book your visit, the admin team will provide you with more information.
Can I come for a twin visit at the weekend?
Sorry, no. Currently the Department is only open Monday to Friday.
I have special needs can I participate?
Yes. Please call us on 020 7188 5555 to discuss your needs so we can accommodate your requirements. In addition, our research facility is accessible by lift and is wheelchair accessible. There are disabled toilets throughout the hospital.
Can my carer come with me?
Yes. Please let us know when you book your appointment.
Will I be able to take part in any publicity?
From time to time we hold media / publicity events / press conferences or take part in documentaries. Alternatively, we may be approached by third parties who are interested in contacting twins. We never give your personal details out but will always contact you directly (usually via email) to ask if you are interested in taking part.
Can I join the registry without my twin?
In order to determine the relative importance of genetic and environmental factors, researchers need to compare identical twins with non-identical twins for the trait of interest. For this reason we are sorry but we need both twins to join the registry together.
Can I come on a twin visit without my twin?
In order to determine the relative importance of genetic and environmental factors, researchers need to compare identical twins with non-identical twins for the trait of interest at the same time point- however in some circumstances you and your twin can come at different times for a twin visit. Lone twins who previously took part in our research together are invited to continue coming on visits alone as they are still able to contribute valuably to the research.
Can I complete a questionnaire even if my twin doesn’t?
Yes! Although we would rather have both of you participating, your questionnaire data will still be useful.
How does the Department of Twin Research keep in touch with twins?
We will normally call you or email you and we also send texts from time to time. We may also write to you or send you questionnaires, so it is important for us to have your up-to-date contact information. You will also receive an annual newsletter and enewsletters throughout the year which will keep you informed of our research findings and studies. Finally, you can find us on facebook, twitter and YouTube with regular updates and feeds.
What happens if I join the registry but then wish to withdraw?
You are free to withdraw at any stage without any explanation. If you withdraw, you would have no further contact from the Department of Twin Research unless you request our newsletter only.
You can withdraw by contacting the Admin Team on 020 7188 5555
or by emailing us on firstname.lastname@example.org
or alternatively writing to:
The Admin Team,
Department of Twin Research,
St. Thomas’ Hospital,
Westminster Bridge Road,
If at any time you wish to rejoin the registry we will be happy to reactivate your records. Please see Question 3 to find out what happens to your data and samples after you withdraw.
3. Data & Samples
What happens to the data & samples you collect?
All clinical measurements, questionnaire data and biological samples including DNA will be stored centrally and securely. We will ensure that all personal data and results are anonymised and cannot lead to the identification of a single individual.
What happens to my samples after I donate them?
Immediately after collection, blood is centrifuged and separated into various components such as serum, plasma and white cells. Part of the serum and all plasma samples are stored in freezers at a low temperature. Other components are sent for glucose, lipids, and cholesterol tests. From the white cells we extract and store the DNA, which is essential for all our research.
How do you use the DNA?
Some of the DNA is stored, and some of the DNA is analysed so that researchers can make associations between people with certain conditions such as osteoporosis and the presence or absence of certain genetic variations. The researchers look for differences in the members of the TwinsUK registry as a whole, but not as individuals.
Because our health is made up of the interaction of thousands of genes with numerous life-style factors, currently we are unable to obtain any clinically useful genetic information from just one person. Ultimately we hope to find the genes that may be responsible for many of our common diseases.
Will DNA be used in cloning experiments?
Your DNA will NOT be used for any experiments with regard to human cloning.
Do I have to donate blood for DNA?
The premise of twin studies is the identification of genetic similarities or differences between twins. For this reason, donating blood for DNA extraction is an essential part of our research. Giving blood for DNA is of course voluntary, but you may not be able to carry on participating in the majority our research if you decide not to.
What happens to my data & samples if I withdraw?
If you decide to withdraw, your previously collected samples and data cannot be removed or destroyed because of the complex nature in the way anonymised data and samples are stored and distributed. All your personal information will be held for archival purposes only and we will continue to preserve confidentiality and security of this data.
4. Research Results
What results will I receive?
Our twin research programme aims to discover the genetic and environmental basis of age-related complex disease and traits, and is not a clinical testing programme. Some of the information and data that we collect at the visit is of no clinical significance as it is still in the research phase (such as the flora ‘stool sample’ study). This means that we do not yet know the significance of the results, and at present neither we, nor your GP, would be able to interpret them. This is summarised on our research consent form as follows “the results of these investigations are unlikely to have any implications for me personally”. However, we are happy that we have received ethics approval to give you a set of clinically useful results for you and your GP from some of the tests that we undertake – including blood pressure, bone density, general blood tests, glucose, cholesterol and renal and liver function tests. You will receive these results between 4 and 6 weeks after your visit. An example of a results letter can be seen by CLICKING HERE. In addition, you will get verbal feedback/advice for some of the tests such as the eye test, grip strength test and lung function test.
Will I receive Genetic results?
At present, we cannot provide you with genetic information, because the laboratories where our research takes place are not certified to provide clinical genetic information. Typically a clinical laboratory would examine an individual sample for one specific gene, whilst our research laboratory analyses thousands of variations across the genome. The researchers look for differences in the members of the TwinsUK registry as a whole, but not as individuals.
5. Ethical standards and confidentiality
Is the research approved?
Yes. All our research is ethically and scientifically approved by the London – Westminster NRES Committee who examine all research applications to ensure the research is ethical and safe for volunteers. You will also receive an approved Volunteer Information Sheet and a Consent form for every study you take part in. Please feel free to discuss the research with friends, family or your GP if you wish to do so. If there is anything that is not clear or if you would like to have more information we will be happy to discuss this with you.
How are you funded?
We are funded via grants from many organisations and charities including the Wellcome Trust, National Institute for Health Research (NIHR), European Commission, Medical Research Council (MRC) and Chronic Disease Research Foundation (CDRF). Smaller projects may be funded by commercial organisations who offer valuable expertise and resources for researchers.
Will you make money from our data?
The Department occasionally collaborates with commercial companies to share expertise. In the rare event of any commercial profits, funds will come back to the hospital and the university for the purpose of further advancement of research.
Who else has access to my personal information / data?
Other approved academic centres and commercial companies – who are collaborating with us in our research – may request access and have rights to the data, including DNA, that we have collected. However, data that is shared is always anonymised.
Are all research collaborators bona fide scientists?
Yes. The anonymised resource is only available to bona fide researchers and access is strictly controlled by a dedicated team of medical and research experts at the Department of Twin Research (DTR) Senior Management Group who assess the potential benefits of the proposed research projects before entering into a legal agreement with the collaborator. On approval, the anonymised data and samples are released to researchers. All researchers are then required to publish their findings and return any valuable results to the DTR so they are available for other scientists to use.
Who owns the data?
The data/intellectual property collected as a result of your participation will always reside with the Hospital and Kings College London. You will not have claim to either the material that we collected or the results arising from the study. Any publications from the twin resource are made available via our website / E-News updates and Annual Newsletter.
Will my taking part in this study be kept confidential?
Yes. We act and comply according to all the principles of the Data Protection Act (1998) and KCL data policies. In summary:
- All information collected about you during the course of the research will be kept strictly confidential. There is a dedicated data management team to ensure that correct procedures are in place at all times.
- Your personal details are kept on a separate database to your clinical and genetic data. A unique participant identifier is used for all clinical and genetic data which is completely anonymous.
- The risks of volunteers being identified inadvertently by researchers is extremely low and is continually reviewed.
Will insurance companies have access to my genetic information?
No. Insurance companies or employers will not have any access to information or samples collected from you. All data is stored centrally in an anonymised database that can only be accessed with passwords. The Department of Twin Research will be the only institution that will be able to link a study number with your personal details.