Background: Gene-environment interaction studies offer the prospect of robust causal inference through both gene
identification and instrumental variable approaches. As such they are a major and much needed development. However,
conducting these studies using traditional methods, which require direct participant contact, is resource intensive. The
ability to conduct gene-environment interaction studies remotely would reduce costs and increase capacity.
Aim: To develop a platform for the remote conduct of gene-environment interaction studies.
Methods: A random sample of 15,000 men and women aged 50+ years and living in Cardiff, South Wales, of whom 6,012
were estimated to have internet connectivity, were mailed inviting them to visit a web-site to join a study of successful
ageing. Online consent was obtained for questionnaire completion, cognitive testing, re-contact, record linkage and
genotyping. Cognitive testing was conducted using the Cardiff Cognitive Battery. Bio-sampling was randomised to blood
spot, buccal cell or no request.
Results: A heterogeneous sample of 663 (4.5% of mailed sample and 11% of internet connected sample) men and women
(47% female) aged 50–87 years (median = 61 yrs) from diverse backgrounds (representing the full range of deprivation
scores) was recruited. Bio-samples were donated by 70% of those agreeing to do so. Self report questionnaires and
cognitive tests showed comparable distributions to those collected using face-to-face methods. Record linkage was
achieved for 99.9% of participants.
Conclusion: This study has demonstrated that remote methods are suitable for the conduct of gene-environment
interaction studies. Up-scaling these methods provides the opportunity to increase capacity for large-scale geneenvironment
interaction studies.