TwinsUK’s Twinclusion Study Helps to Fill in the Gaps in Health Research

7th July 2026 – by Molly Kiley

To study ageing and long-term health, researchers need detailed samples and data from a wide range of people to understand the health and genetic factors that affect the full population. However, individuals who are elderly, sick, or with carer responsibilities are often unable to take part in health research as the time and travel required are too demanding. Without information from these people, researchers may be missing important factors that influence health, disease, and ageing. Within TwinsUK research cohort, these individuals have also often been participating for the longest and have already provided dozens of samples, visits, and valuable research data.

TwinsUK has contributed to research on ageing and health conditions over the last 30 years with samples and data from 16,000 participants, creating a biobank of over 700,000 biological samples. Thanks to highly engaged participants, TwinsUK has grown to be the most clinically detailed adult twin registry in the world and helped researchers study how environment, genetics, and ageing affect health and resilience.

To address the issue of missing data from elderly, carer, and people unable to travel in health research, TwinsUK created the Twinclusion study to collect samples and research data from participants who would otherwise not be able to continue to participate in TwinsUK’s research. Through this study, TwinsUK participants over the age of 60 who are no longer able to travel to attend research visits can provide samples and health questionnaires through a home postal kit.

Over 250 twins have taken part in Twinclusion over the last two years, providing over 600 samples to add to TwinsUK’s biobank as a resource for health research. One participating twin Ros shared her experience with the Twinclusion study:

‘To be able to take part in the Twinclusion study was a really interesting experience and I felt really privileged to have taken part. My twin sister lives in Scotland and I live in Northamptonshire and at the time we were trying to sort out a date to go to London I was also working and we were finding really hard to find a date that suited us both to go to London… But I was really excited to get an email a few months later asking if I would like to take part in the Twinclusion research/study at home. I immediately replied Yes please and was sent an email explaining what I would need to do, along with videos links to show me how to do the various tests. The Twinclusion box was sent out with the practical things I needed to use and return along with a prepaid envelope.’

TwinsUK members can take part in Twinclusion either with their twin or on their own if their twin is not interested or no longer able to take part. By taking part in Twinclusion, individuals are helping to fill in the gaps in research on ageing and resilience that most research studies aren’t able to include. As Ros noted about her participation:

‘I know my contributions is only a very little bit towards research, but a small seed with other seeds, grows into something really interesting and exciting and I truly hope in some way I have helped. I would definitely like to do anymore home research if I’m asked.’

The Twinclusion study will continue through 2028. TwinsUK members over the age of 60 who have previously taken part in TwinsUK research studies or questionnaires and are no longer able to attend visits are encouraged to email twinsUK@kcl.ac.uk to express their interest in the Twinclusion study.