Cohort/Data Description


There are currently 12,000 twins registered on our database, of which 9,000 are actively participating. The twins are aged 16 to 100 with approximately equal numbers of identical (MZ) and non-identical (DZ) twins and are predominantly female (80%) for historical reasons. Clinical, physiological, behavioural and lifestyle data is collected at either twin visits  to the DTR or via self-administered questionnaires, which volunteers complete either once or twice a year via the post or email.  All studies  have ethical approval from the Guy’s and St Thomas’ (GSTT) Ethics Committee.


Extensive clinical, physiological, behavioural and lifestyle data is available, many taken at multiple time-points, as well as hundreds of phenotypes related to common diseases . The cohort is one of the most highly and deeply genotyped in the world.

Please click here to access a list of phenotypes accessible to the scientific community.

A summary of biochemical and genetic data available on a large number of twins is listed below:

Genetic and Molecular Data

  • GWAS Illumina ~6000
  • Gene Expression ~850 (fat, LCL, skin)
  • Sequence Data (future)
  • Metabolic Data (~1200 twins)

Biochemical Samples

  • DNA
  • Cell Lines
  • Serum
  • Plasma
  • Urine

The DTR would like to state that under the Open Access Model it cannot guarantee data exclusivity.

If there is a possibility of projects overlapping or other investigators/groups working on related topics, the TwinsUK Resource Committee may facilitate contact with these groups and invite you to discuss your ideas before you proceed with your request.

For scientists who fund the collection of specific new data, we establish an embargo period whereby the scientist can work exclusively on the data for either twelve months or after the first publication is accepted (whichever comes first). After this period the embargo will be terminated and the data will be available to the scientific community.