Join us in this research seminar to explore how polygenic scores can illuminate the role of genetics in mortality rates.

The identification of causal relationships between specific genes and social, behavioral, and health outcomes is challenging due to environmental confounding from population stratification and dynastic genetic effects. We introduce the phenotype differences model to compare siblings and estimate the causal effect of genetic predictors using just a single individual's genotype. We show that, under plausible assumptions, the phenotype differences model provides unbiased and consistent estimates of genetic effects. We then utilize the phenotype differences model to estimate the effects of 40 polygenic scores on premature mortality using asymmetrically genotyped sibling pairs in the Wisconsin Longitudinal Study. We find that twelve polygenic scores related to self-rated health, body mass index, education, cognition, depression, life satisfaction, smoking behavior, and chronic obstructive pulmonary disease have a meaningful impact on mortality outcomes. When we combine information across multiple polygenic scores, the sibling in a pair who inherited more longevity-increasing DNA from their parents on average lived 9 months longer and was 7 pp (12%) more likely to survive until age 75 than their brother/sister.

The seminar will commence at 1pm. A light lunch will be served from 12.30pm.

Meet our speaker and chair

Sam Trejo is Assistant Professor of Sociology at Princeton University. A sociologist and demographer by training, he is interested in how social and biological factors jointly shape human development across the life course. He specialises in quasi-experimental, computational and biosocial quantitative methods, and his research typically utilizes large administrative datasets and longitudinal studies containing molecular genetic data. His presentation at LSE will focus on one branch of his research, which surround polygenic scores, measures meant to summarize a person’s genetic disposition for a trait (ranging from height to depression to cognitive ability). In that area, he studies how the social environment mediates, moderates and confounds associations between genes and outcomes. Dr Trejo is currently writing a book with Dr Martschenko – a bioethicist specializing in mixed methods and critical theory – in which they unpack social, ethical, and policy issues related to the DNA revolution.

Emilie Courtin is Assistant Professor of Health Policy. She co-directs the MSc Health Policy, Planning and Financing (HPPF) programme. Her research combines social epidemiology and social policy to assess how non-medical policies influence health, disease and health care use.

Hashtag: #PrematureMortality

This is the second event of the social to biological interdisciplinary seminar series, hosted across LSE Health, Oxford, UCL and Imperial. The aim of the seminar is to promote interdisciplinary research across social and biological sciences to advance our understanding of the drivers of health and ageing across the life course. For more information about future events and to be added to our mailing list, please contact Emilie Courtin.