Moana Beyer

Twin registries worldwide increasingly function as large-scale research infrastructures, enabling standardized phenotyping across the lifespan, integration of biological and environmental data streams, and international cross-cohort collaborative research and replications. This development is also taking place in Germany. The GERman Twin Registry Under Development (GERTRUD; www.gertrud.info ) was established in 2022 as the first nationwide research platform for recruiting twins and higher order multiples of all ages within Germany to support the large-scale genetically informative psychological, sociological, health, and neuroscience twin research at national and international levels. GERTRUD is being developed as a modular infrastructure that supports classical and extended twin family designs, combining annual core survey waves with optional embedded modules for intensive phenotyping (e.g., neuroimaging, smartphone-based assessments), biosampling, and linkage of participants’ residential context to external geographic datasets via geospatial information systems (GIS). To operate within Germany’s stringent data protection landscape, GERTRUD implements project-specific pseudonymisation, role-based access control, and contract-governed remote analysis access. This article describes GERTRUD’s governance and legal–technical framework, its multisource data architecture, and the potential for collaboration across Germany and internationally. Examples of early data implementations further illustrate that the continuously collected multimodal twin data constitute a critical asset, essential for successful harmonization, replication, and collaborative and integrative behavioral genetics research.

Ambient air pollution, specifically particulate matter (PM10 and PM2.5), is a major environmental concern with well-documented links to health and life satisfaction. While the causal pathways and mechanisms underlying these associations are actively being researched, the contribution of genetic and environmental familial factors to these links remains largely unexplored. In this regard, emerging adulthood is intriguing, as young adults increasingly establish lives outside parental homes, allowing for greater separation of familial and individual-specific effects. To leverage this time window, we analysed data from 4,504 young adult twins in the TwinLife study (Mage=23.04 years, SD=0.82; Nmonozygotic=2,249; Ndizygotic=2,255), assessed up to six times between 2014 and 2022. Twin comparison analysis was used to decompose the population link between PM10 and life satisfaction to test whether the effect runs between families (between-pair) or within families (within-pair), and whether these effects are zygosity-, age-, and measurement-specific. The effect of PM10 on life satisfaction ran between families, suggesting that shared factors, such as indirect effects of familial SES or neighbourhood characteristics, may be of importance. In monozygotic twins, the between-pair negative effect of PM10 on life satisfaction strengthened with age (b=-0.006, SE=0.003) and year of measurement (b=-0.011, SE=0.004). Controlling for between-pair differences, the within-pair effect was significant within monozygotic twins (b=-0.088, SE=0.030), and not within dizygotic twins (b=0.006, SE=0.041), suggesting the possibility of genetic confounding and a small but quasi-causal relationship between PM10 and life satisfaction in young adulthood. Target interventions, thus, should include both addressing the specific factors shared by twin families and the development of emissions-reduction strategies.

Zusammenfassung: Unsere Umwelt umgibt uns täglich in all ihren Facetten – von ruhigen Grünflächen über belebte Straßen bis hin zu Luftqualität, Lichteinflüssen und sozialen Netzwerken. Umweltneurowissenschaften untersuchen, wie physische, soziale und kulturelle Bedingungen mit neuronalen und kognitiven Prozessen interagieren.